diff --git a/scm-core/src/main/java/sonia/scm/plugin/AvailablePlugin.java b/scm-core/src/main/java/sonia/scm/plugin/AvailablePlugin.java
index 6596fa4751..2353f5a10e 100644
--- a/scm-core/src/main/java/sonia/scm/plugin/AvailablePlugin.java
+++ b/scm-core/src/main/java/sonia/scm/plugin/AvailablePlugin.java
@@ -1,11 +1,19 @@
 package sonia.scm.plugin;
 
+import com.google.common.base.Preconditions;
+
 public class AvailablePlugin implements Plugin {
 
   private final AvailablePluginDescriptor pluginDescriptor;
+  private final boolean pending;
 
   public AvailablePlugin(AvailablePluginDescriptor pluginDescriptor) {
+    this(pluginDescriptor, false);
+  }
+
+  private AvailablePlugin(AvailablePluginDescriptor pluginDescriptor, boolean pending) {
     this.pluginDescriptor = pluginDescriptor;
+    this.pending = pending;
   }
 
   @Override
@@ -17,4 +25,13 @@ public class AvailablePlugin implements Plugin {
   public PluginState getState() {
     return PluginState.AVAILABLE;
   }
+
+  public boolean isPending() {
+    return pending;
+  }
+
+  public AvailablePlugin install() {
+    Preconditions.checkState(!pending, "installation is already pending");
+    return new AvailablePlugin(pluginDescriptor, true);
+  }
 }
diff --git a/scm-core/src/main/java/sonia/scm/plugin/Plugin.java b/scm-core/src/main/java/sonia/scm/plugin/Plugin.java
index e39d23c046..40f5ec2b49 100644
--- a/scm-core/src/main/java/sonia/scm/plugin/Plugin.java
+++ b/scm-core/src/main/java/sonia/scm/plugin/Plugin.java
@@ -3,6 +3,14 @@ package sonia.scm.plugin;
 public interface Plugin {
 
   PluginDescriptor getDescriptor();
+
+  /**
+   * Returns plugin state.
+   *
+   * @deprecated State is now derived from concrete plugin implementations
+   * @return plugin state
+   */
+  @Deprecated
   PluginState getState();
 
 }
diff --git a/scm-core/src/main/java/sonia/scm/plugin/PluginManager.java b/scm-core/src/main/java/sonia/scm/plugin/PluginManager.java
index 235e360547..b7b8f69519 100644
--- a/scm-core/src/main/java/sonia/scm/plugin/PluginManager.java
+++ b/scm-core/src/main/java/sonia/scm/plugin/PluginManager.java
@@ -80,4 +80,9 @@ public interface PluginManager {
    * @param restartAfterInstallation restart context after plugin installation
    */
   void install(String name, boolean restartAfterInstallation);
+
+  /**
+   * Install all pending plugins and restart the scm context.
+   */
+  void installPendingAndRestart();
 }
diff --git a/scm-core/src/test/java/sonia/scm/plugin/AvailablePluginTest.java b/scm-core/src/test/java/sonia/scm/plugin/AvailablePluginTest.java
new file mode 100644
index 0000000000..bfdf74fdb1
--- /dev/null
+++ b/scm-core/src/test/java/sonia/scm/plugin/AvailablePluginTest.java
@@ -0,0 +1,32 @@
+package sonia.scm.plugin;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+@ExtendWith(MockitoExtension.class)
+class AvailablePluginTest {
+
+  @Mock
+  private AvailablePluginDescriptor descriptor;
+
+  @Test
+  void shouldReturnNewPendingPluginOnInstall() {
+    AvailablePlugin plugin = new AvailablePlugin(descriptor);
+    assertThat(plugin.isPending()).isFalse();
+
+    AvailablePlugin installed = plugin.install();
+    assertThat(installed.isPending()).isTrue();
+  }
+
+  @Test
+  void shouldThrowIllegalStateExceptionIfAlreadyPending() {
+    AvailablePlugin plugin = new AvailablePlugin(descriptor).install();
+    assertThrows(IllegalStateException.class, () -> plugin.install());
+  }
+
+}
diff --git a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/AvailablePluginResource.java b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/AvailablePluginResource.java
index e6c4ef8410..e54c6cf85e 100644
--- a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/AvailablePluginResource.java
+++ b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/AvailablePluginResource.java
@@ -10,7 +10,6 @@ import sonia.scm.plugin.PluginPermissions;
 import sonia.scm.web.VndMediaType;
 
 import javax.inject.Inject;
-import javax.ws.rs.Consumes;
 import javax.ws.rs.GET;
 import javax.ws.rs.POST;
 import javax.ws.rs.Path;
@@ -74,7 +73,7 @@ public class AvailablePluginResource {
     PluginPermissions.read().check();
     Optional<AvailablePlugin> plugin = pluginManager.getAvailable(name);
     if (plugin.isPresent()) {
-      return Response.ok(mapper.map(plugin.get())).build();
+      return Response.ok(mapper.mapAvailable(plugin.get())).build();
     } else {
       throw notFound(entity(InstalledPluginDescriptor.class, name));
     }
diff --git a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/InstalledPluginResource.java b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/InstalledPluginResource.java
index 7c3f972a7b..893d09a51a 100644
--- a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/InstalledPluginResource.java
+++ b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/InstalledPluginResource.java
@@ -73,7 +73,7 @@ public class InstalledPluginResource {
     PluginPermissions.read().check();
     Optional<InstalledPlugin> pluginDto = pluginManager.getInstalled(name);
     if (pluginDto.isPresent()) {
-      return Response.ok(mapper.map(pluginDto.get())).build();
+      return Response.ok(mapper.mapInstalled(pluginDto.get())).build();
     } else {
       throw notFound(entity(InstalledPluginDescriptor.class, name));
     }
diff --git a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/PluginDto.java b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/PluginDto.java
index 07ccb3203e..bf20d1b67e 100644
--- a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/PluginDto.java
+++ b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/PluginDto.java
@@ -11,6 +11,7 @@ import java.util.Set;
 @Getter
 @Setter
 @NoArgsConstructor
+@SuppressWarnings("squid:S2160") // we do not need equals for dto
 public class PluginDto extends HalRepresentation {
 
   private String name;
@@ -20,6 +21,7 @@ public class PluginDto extends HalRepresentation {
   private String author;
   private String category;
   private String avatarUrl;
+  private boolean pending;
   private Set<String> dependencies;
 
   public PluginDto(Links links) {
diff --git a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/PluginDtoCollectionMapper.java b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/PluginDtoCollectionMapper.java
index 276eddfab6..bcfbce3f04 100644
--- a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/PluginDtoCollectionMapper.java
+++ b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/PluginDtoCollectionMapper.java
@@ -5,10 +5,8 @@ import de.otto.edison.hal.Embedded;
 import de.otto.edison.hal.HalRepresentation;
 import de.otto.edison.hal.Links;
 import sonia.scm.plugin.AvailablePlugin;
-import sonia.scm.plugin.PluginInformation;
 import sonia.scm.plugin.InstalledPlugin;
 
-import java.util.Collection;
 import java.util.List;
 
 import static de.otto.edison.hal.Embedded.embeddedBuilder;
@@ -27,12 +25,12 @@ public class PluginDtoCollectionMapper {
   }
 
   public HalRepresentation mapInstalled(List<InstalledPlugin> plugins) {
-    List<PluginDto> dtos = plugins.stream().map(mapper::map).collect(toList());
+    List<PluginDto> dtos = plugins.stream().map(mapper::mapInstalled).collect(toList());
     return new HalRepresentation(createInstalledPluginsLinks(), embedDtos(dtos));
   }
 
   public HalRepresentation mapAvailable(List<AvailablePlugin> plugins) {
-    List<PluginDto> dtos = plugins.stream().map(mapper::map).collect(toList());
+    List<PluginDto> dtos = plugins.stream().map(mapper::mapAvailable).collect(toList());
     return new HalRepresentation(createAvailablePluginsLinks(), embedDtos(dtos));
   }
 
diff --git a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/PluginDtoMapper.java b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/PluginDtoMapper.java
index 193aa3af26..25faf0a101 100644
--- a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/PluginDtoMapper.java
+++ b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/PluginDtoMapper.java
@@ -3,9 +3,11 @@ package sonia.scm.api.v2.resources;
 import de.otto.edison.hal.Links;
 import org.mapstruct.Mapper;
 import org.mapstruct.MappingTarget;
+import sonia.scm.plugin.AvailablePlugin;
+import sonia.scm.plugin.InstalledPlugin;
 import sonia.scm.plugin.Plugin;
 import sonia.scm.plugin.PluginInformation;
-import sonia.scm.plugin.PluginState;
+import sonia.scm.plugin.PluginPermissions;
 
 import javax.inject.Inject;
 
@@ -20,34 +22,48 @@ public abstract class PluginDtoMapper {
 
   public abstract void map(PluginInformation plugin, @MappingTarget PluginDto dto);
 
-  public PluginDto map(Plugin plugin) {
-    PluginDto dto = createDto(plugin);
+  public PluginDto mapInstalled(InstalledPlugin plugin) {
+    PluginDto dto = createDtoForInstalled(plugin);
+    map(dto, plugin);
+    return dto;
+  }
+
+  public PluginDto mapAvailable(AvailablePlugin plugin) {
+    PluginDto dto = createDtoForAvailable(plugin);
+    map(dto, plugin);
+    dto.setPending(plugin.isPending());
+    return dto;
+  }
+
+  private void map(PluginDto dto, Plugin plugin) {
     dto.setDependencies(plugin.getDescriptor().getDependencies());
     map(plugin.getDescriptor().getInformation(), dto);
     if (dto.getCategory() == null) {
       dto.setCategory("Miscellaneous");
     }
-    return dto;
   }
 
-  private PluginDto createDto(Plugin plugin) {
-    Links.Builder linksBuilder;
+  private PluginDto createDtoForAvailable(AvailablePlugin plugin) {
+    PluginInformation information = plugin.getDescriptor().getInformation();
 
-    PluginInformation pluginInformation = plugin.getDescriptor().getInformation();
+    Links.Builder links = linkingTo()
+      .self(resourceLinks.availablePlugin()
+        .self(information.getName()));
 
-    if (plugin.getState() != null && plugin.getState().equals(PluginState.AVAILABLE)) {
-      linksBuilder = linkingTo()
-        .self(resourceLinks.availablePlugin()
-          .self(pluginInformation.getName(), pluginInformation.getVersion()));
-
-      linksBuilder.single(link("install", resourceLinks.availablePlugin().install(pluginInformation.getName(), pluginInformation.getVersion())));
-    }
-    else {
-      linksBuilder = linkingTo()
-        .self(resourceLinks.installedPlugin()
-          .self(pluginInformation.getName()));
+    if (!plugin.isPending() && PluginPermissions.manage().isPermitted()) {
+      links.single(link("install", resourceLinks.availablePlugin().install(information.getName())));
     }
 
-    return new PluginDto(linksBuilder.build());
+    return new PluginDto(links.build());
+  }
+
+  private PluginDto createDtoForInstalled(InstalledPlugin plugin) {
+    PluginInformation information = plugin.getDescriptor().getInformation();
+
+    Links.Builder links = linkingTo()
+      .self(resourceLinks.installedPlugin()
+        .self(information.getName()));
+
+    return new PluginDto(links.build());
   }
 }
diff --git a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/ResourceLinks.java b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/ResourceLinks.java
index 268f5f8619..6d49ca1fb6 100644
--- a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/ResourceLinks.java
+++ b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/ResourceLinks.java
@@ -6,6 +6,7 @@ import javax.inject.Inject;
 import java.net.URI;
 import java.net.URISyntaxException;
 
+@SuppressWarnings("squid:S1192") // string literals should not be duplicated
 class ResourceLinks {
 
   private final ScmPathInfoStore scmPathInfoStore;
@@ -694,12 +695,12 @@ class ResourceLinks {
       availablePluginLinkBuilder = new LinkBuilder(pathInfo, PluginRootResource.class, AvailablePluginResource.class);
     }
 
-    String self(String name, String version) {
-      return availablePluginLinkBuilder.method("availablePlugins").parameters().method("getAvailablePlugin").parameters(name, version).href();
+    String self(String name) {
+      return availablePluginLinkBuilder.method("availablePlugins").parameters().method("getAvailablePlugin").parameters(name).href();
     }
 
-    String install(String name, String version) {
-      return availablePluginLinkBuilder.method("availablePlugins").parameters().method("installPlugin").parameters(name, version).href();
+    String install(String name) {
+      return availablePluginLinkBuilder.method("availablePlugins").parameters().method("installPlugin").parameters(name).href();
     }
   }
 
diff --git a/scm-webapp/src/main/java/sonia/scm/plugin/DefaultPluginManager.java b/scm-webapp/src/main/java/sonia/scm/plugin/DefaultPluginManager.java
index 756f1fb741..807eaac317 100644
--- a/scm-webapp/src/main/java/sonia/scm/plugin/DefaultPluginManager.java
+++ b/scm-webapp/src/main/java/sonia/scm/plugin/DefaultPluginManager.java
@@ -67,6 +67,7 @@ public class DefaultPluginManager implements PluginManager {
   private final PluginLoader loader;
   private final PluginCenter center;
   private final PluginInstaller installer;
+  private final List<PendingPluginInstallation> pendingQueue = new ArrayList<>();
 
   @Inject
   public DefaultPluginManager(ScmEventBus eventBus, PluginLoader loader, PluginCenter center, PluginInstaller installer) {
@@ -83,6 +84,15 @@ public class DefaultPluginManager implements PluginManager {
       .stream()
       .filter(filterByName(name))
       .filter(this::isNotInstalled)
+      .map(p -> getPending(name).orElse(p))
+      .findFirst();
+  }
+
+  private Optional<AvailablePlugin> getPending(String name) {
+    return pendingQueue
+      .stream()
+      .map(PendingPluginInstallation::getPlugin)
+      .filter(filterByName(name))
       .findFirst();
   }
 
@@ -104,7 +114,11 @@ public class DefaultPluginManager implements PluginManager {
   @Override
   public List<AvailablePlugin> getAvailable() {
     PluginPermissions.read().check();
-    return center.getAvailable().stream().filter(this::isNotInstalled).collect(Collectors.toList());
+    return center.getAvailable()
+      .stream()
+      .filter(this::isNotInstalled)
+      .map(p -> getPending(p.getDescriptor().getInformation().getName()).orElse(p))
+      .collect(Collectors.toList());
   }
 
   private <T extends Plugin> Predicate<T> filterByName(String name) {
@@ -129,11 +143,28 @@ public class DefaultPluginManager implements PluginManager {
         throw ex;
       }
     }
-    if (restartAfterInstallation) {
-      eventBus.post(new RestartEvent(PluginManager.class, "plugin installation"));
+
+    if (!pendingInstallations.isEmpty()) {
+      if (restartAfterInstallation) {
+        restart("plugin installation");
+      } else {
+        pendingQueue.addAll(pendingInstallations);
+      }
     }
   }
 
+  @Override
+  public void installPendingAndRestart() {
+    PluginPermissions.manage().check();
+    if (!pendingQueue.isEmpty()) {
+      restart("install pending plugins");
+    }
+  }
+
+  private void restart(String cause) {
+    eventBus.post(new RestartEvent(PluginManager.class, cause));
+  }
+
   private void cancelPending(List<PendingPluginInstallation> pendingInstallations) {
     pendingInstallations.forEach(PendingPluginInstallation::cancel);
   }
@@ -144,8 +175,12 @@ public class DefaultPluginManager implements PluginManager {
     return plugins;
   }
 
+  private boolean isInstalledOrPending(String name) {
+    return getInstalled(name).isPresent() || getPending(name).isPresent();
+  }
+
   private void collectPluginsToInstall(List<AvailablePlugin> plugins, String name) {
-    if (!getInstalled(name).isPresent()) {
+    if (!isInstalledOrPending(name)) {
       AvailablePlugin plugin = getAvailable(name).orElseThrow(() -> NotFoundException.notFound(entity(AvailablePlugin.class, name)));
 
       Set<String> dependencies = plugin.getDescriptor().getDependencies();
@@ -157,7 +192,7 @@ public class DefaultPluginManager implements PluginManager {
 
       plugins.add(plugin);
     } else {
-      LOG.info("plugin {} is already installed, skipping installation", name);
+      LOG.info("plugin {} is already installed or installation is pending, skipping installation", name);
     }
   }
 }
diff --git a/scm-webapp/src/main/java/sonia/scm/plugin/PluginInstaller.java b/scm-webapp/src/main/java/sonia/scm/plugin/PluginInstaller.java
index 71a4c35a3a..88b1a469ba 100644
--- a/scm-webapp/src/main/java/sonia/scm/plugin/PluginInstaller.java
+++ b/scm-webapp/src/main/java/sonia/scm/plugin/PluginInstaller.java
@@ -33,7 +33,7 @@ class PluginInstaller {
       Files.copy(input, file);
 
       verifyChecksum(plugin, input.hash(), file);
-      return new PendingPluginInstallation(plugin, file);
+      return new PendingPluginInstallation(plugin.install(), file);
     } catch (IOException ex) {
       cleanup(file);
       throw new PluginDownloadException("failed to download plugin", ex);
diff --git a/scm-webapp/src/test/java/sonia/scm/api/v2/resources/AvailablePluginResourceTest.java b/scm-webapp/src/test/java/sonia/scm/api/v2/resources/AvailablePluginResourceTest.java
index 2a473ea63e..8023bee4dd 100644
--- a/scm-webapp/src/test/java/sonia/scm/api/v2/resources/AvailablePluginResourceTest.java
+++ b/scm-webapp/src/test/java/sonia/scm/api/v2/resources/AvailablePluginResourceTest.java
@@ -117,7 +117,7 @@ class AvailablePluginResourceTest {
 
       PluginDto pluginDto = new PluginDto();
       pluginDto.setName("pluginName");
-      when(mapper.map(plugin)).thenReturn(pluginDto);
+      when(mapper.mapAvailable(plugin)).thenReturn(pluginDto);
 
       MockHttpRequest request = MockHttpRequest.get("/v2/plugins/available/pluginName");
       request.accept(VndMediaType.PLUGIN);
diff --git a/scm-webapp/src/test/java/sonia/scm/api/v2/resources/InstalledPluginResourceTest.java b/scm-webapp/src/test/java/sonia/scm/api/v2/resources/InstalledPluginResourceTest.java
index c5868a1211..7fa0081c5c 100644
--- a/scm-webapp/src/test/java/sonia/scm/api/v2/resources/InstalledPluginResourceTest.java
+++ b/scm-webapp/src/test/java/sonia/scm/api/v2/resources/InstalledPluginResourceTest.java
@@ -110,7 +110,7 @@ class InstalledPluginResourceTest {
 
       PluginDto pluginDto = new PluginDto();
       pluginDto.setName("pluginName");
-      when(mapper.map(installedPlugin)).thenReturn(pluginDto);
+      when(mapper.mapInstalled(installedPlugin)).thenReturn(pluginDto);
 
       MockHttpRequest request = MockHttpRequest.get("/v2/plugins/installed/pluginName");
       request.accept(VndMediaType.PLUGIN);
diff --git a/scm-webapp/src/test/java/sonia/scm/api/v2/resources/PluginDtoMapperTest.java b/scm-webapp/src/test/java/sonia/scm/api/v2/resources/PluginDtoMapperTest.java
index 3eaeb7a2cc..5cf6bdd45a 100644
--- a/scm-webapp/src/test/java/sonia/scm/api/v2/resources/PluginDtoMapperTest.java
+++ b/scm-webapp/src/test/java/sonia/scm/api/v2/resources/PluginDtoMapperTest.java
@@ -1,15 +1,20 @@
 package sonia.scm.api.v2.resources;
 
 import com.google.common.collect.ImmutableSet;
+import org.apache.shiro.subject.Subject;
+import org.apache.shiro.util.ThreadContext;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Answers;
 import org.mockito.InjectMocks;
-import org.mockito.Mockito;
+import org.mockito.Mock;
 import org.mockito.junit.jupiter.MockitoExtension;
-import sonia.scm.plugin.Plugin;
-import sonia.scm.plugin.PluginDescriptor;
+import sonia.scm.plugin.AvailablePlugin;
+import sonia.scm.plugin.AvailablePluginDescriptor;
+import sonia.scm.plugin.InstalledPlugin;
 import sonia.scm.plugin.PluginInformation;
-import sonia.scm.plugin.PluginState;
 
 import java.net.URI;
 
@@ -26,6 +31,19 @@ class PluginDtoMapperTest {
   @InjectMocks
   private PluginDtoMapperImpl mapper;
 
+  @Mock
+  private Subject subject;
+
+  @BeforeEach
+  void bindSubject() {
+    ThreadContext.bind(subject);
+  }
+
+  @AfterEach
+  void unbindSubject() {
+    ThreadContext.unbindSubject();
+  }
+
   @Test
   void shouldMapInformation() {
     PluginInformation information = createPluginInformation();
@@ -54,27 +72,42 @@ class PluginDtoMapperTest {
 
   @Test
   void shouldAppendInstalledSelfLink() {
-    Plugin plugin = createPlugin(PluginState.INSTALLED);
+    InstalledPlugin plugin = createInstalled();
 
-    PluginDto dto = mapper.map(plugin);
+    PluginDto dto = mapper.mapInstalled(plugin);
     assertThat(dto.getLinks().getLinkBy("self").get().getHref())
       .isEqualTo("https://hitchhiker.com/v2/plugins/installed/scm-cas-plugin");
   }
 
+  private InstalledPlugin createInstalled(PluginInformation information) {
+    InstalledPlugin plugin = mock(InstalledPlugin.class, Answers.RETURNS_DEEP_STUBS);
+    when(plugin.getDescriptor().getInformation()).thenReturn(information);
+    return plugin;
+  }
+
   @Test
   void shouldAppendAvailableSelfLink() {
-    Plugin plugin = createPlugin(PluginState.AVAILABLE);
+    AvailablePlugin plugin = createAvailable();
 
-    PluginDto dto = mapper.map(plugin);
+    PluginDto dto = mapper.mapAvailable(plugin);
     assertThat(dto.getLinks().getLinkBy("self").get().getHref())
       .isEqualTo("https://hitchhiker.com/v2/plugins/available/scm-cas-plugin");
   }
 
   @Test
-  void shouldAppendInstallLink() {
-    Plugin plugin = createPlugin(PluginState.AVAILABLE);
+  void shouldNotAppendInstallLinkWithoutPermissions() {
+    AvailablePlugin plugin = createAvailable();
 
-    PluginDto dto = mapper.map(plugin);
+    PluginDto dto = mapper.mapAvailable(plugin);
+    assertThat(dto.getLinks().getLinkBy("install")).isEmpty();
+  }
+
+  @Test
+  void shouldAppendInstallLink() {
+    when(subject.isPermitted("plugin:manage")).thenReturn(true);
+    AvailablePlugin plugin = createAvailable();
+
+    PluginDto dto = mapper.mapAvailable(plugin);
     assertThat(dto.getLinks().getLinkBy("install").get().getHref())
       .isEqualTo("https://hitchhiker.com/v2/plugins/available/scm-cas-plugin/install");
   }
@@ -83,31 +116,32 @@ class PluginDtoMapperTest {
   void shouldReturnMiscellaneousIfCategoryIsNull() {
     PluginInformation information = createPluginInformation();
     information.setCategory(null);
-    Plugin plugin = createPlugin(information, PluginState.AVAILABLE);
-    PluginDto dto = mapper.map(plugin);
+    AvailablePlugin plugin = createAvailable(information);
+    PluginDto dto = mapper.mapAvailable(plugin);
     assertThat(dto.getCategory()).isEqualTo("Miscellaneous");
   }
 
   @Test
   void shouldAppendDependencies() {
-    Plugin plugin = createPlugin(PluginState.AVAILABLE);
+    AvailablePlugin plugin = createAvailable();
     when(plugin.getDescriptor().getDependencies()).thenReturn(ImmutableSet.of("one", "two"));
 
-    PluginDto dto = mapper.map(plugin);
+    PluginDto dto = mapper.mapAvailable(plugin);
     assertThat(dto.getDependencies()).containsOnly("one", "two");
   }
 
-  private Plugin createPlugin(PluginState state) {
-    return createPlugin(createPluginInformation(), state);
+  private InstalledPlugin createInstalled() {
+    return createInstalled(createPluginInformation());
   }
 
-  private Plugin createPlugin(PluginInformation information, PluginState state) {
-    Plugin plugin = Mockito.mock(Plugin.class);
-    when(plugin.getState()).thenReturn(state);
-    PluginDescriptor descriptor = mock(PluginDescriptor.class);
+  private AvailablePlugin createAvailable() {
+    return createAvailable(createPluginInformation());
+  }
+
+  private AvailablePlugin createAvailable(PluginInformation information) {
+    AvailablePluginDescriptor descriptor = mock(AvailablePluginDescriptor.class);
     when(descriptor.getInformation()).thenReturn(information);
-    when(plugin.getDescriptor()).thenReturn(descriptor);
-    return plugin;
+    return new AvailablePlugin(descriptor);
   }
 
 }
diff --git a/scm-webapp/src/test/java/sonia/scm/plugin/DefaultPluginManagerTest.java b/scm-webapp/src/test/java/sonia/scm/plugin/DefaultPluginManagerTest.java
index e9469c10d6..322163ee1a 100644
--- a/scm-webapp/src/test/java/sonia/scm/plugin/DefaultPluginManagerTest.java
+++ b/scm-webapp/src/test/java/sonia/scm/plugin/DefaultPluginManagerTest.java
@@ -11,6 +11,7 @@ import org.junit.jupiter.api.Nested;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Answers;
+import org.mockito.ArgumentCaptor;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.junit.jupiter.MockitoExtension;
@@ -22,6 +23,7 @@ import java.util.List;
 import java.util.Optional;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.in;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.Mockito.*;
 
@@ -46,6 +48,14 @@ class DefaultPluginManagerTest {
   @Mock
   private Subject subject;
 
+  @BeforeEach
+  void mockInstaller() {
+    lenient().when(installer.install(any())).then(ic -> {
+      AvailablePlugin plugin = ic.getArgument(0);
+      return new PendingPluginInstallation(plugin.install(), null);
+    });
+  }
+
   @Nested
   class WithAdminPermissions {
 
@@ -180,7 +190,10 @@ class DefaultPluginManagerTest {
 
       manager.install("scm-review-plugin", false);
 
-      verify(installer).install(review);
+      ArgumentCaptor<AvailablePlugin> captor = ArgumentCaptor.forClass(AvailablePlugin.class);
+      verify(installer).install(captor.capture());
+
+      assertThat(captor.getValue().getDescriptor().getInformation().getName()).isEqualTo("scm-review-plugin");
     }
 
     @Test
@@ -230,6 +243,66 @@ class DefaultPluginManagerTest {
       verify(eventBus).post(any(RestartEvent.class));
     }
 
+    @Test
+    void shouldNotSendRestartEventIfNoPluginWasInstalled() {
+      InstalledPlugin gitInstalled = createInstalled("scm-git-plugin");
+      when(loader.getInstalledPlugins()).thenReturn(ImmutableList.of(gitInstalled));
+
+      manager.install("scm-git-plugin", true);
+      verify(eventBus, never()).post(any());
+    }
+
+    @Test
+    void shouldNotInstallAlreadyPendingPlugins() {
+      AvailablePlugin review = createAvailable("scm-review-plugin");
+      when(center.getAvailable()).thenReturn(ImmutableSet.of(review));
+
+      manager.install("scm-review-plugin", false);
+      manager.install("scm-review-plugin", false);
+      // only one interaction
+      verify(installer).install(any());
+    }
+
+    @Test
+    void shouldSendRestartEvent() {
+      AvailablePlugin review = createAvailable("scm-review-plugin");
+      when(center.getAvailable()).thenReturn(ImmutableSet.of(review));
+
+      manager.install("scm-review-plugin", false);
+      manager.installPendingAndRestart();
+
+      verify(eventBus).post(any(RestartEvent.class));
+    }
+
+    @Test
+    void shouldNotSendRestartEventWithoutPendingPlugins() {
+      manager.installPendingAndRestart();
+
+      verify(eventBus, never()).post(any());
+    }
+
+    @Test
+    void shouldReturnSingleAvailableAsPending() {
+      AvailablePlugin review = createAvailable("scm-review-plugin");
+      when(center.getAvailable()).thenReturn(ImmutableSet.of(review));
+
+      manager.install("scm-review-plugin", false);
+
+      Optional<AvailablePlugin> available = manager.getAvailable("scm-review-plugin");
+      assertThat(available.get().isPending()).isTrue();
+    }
+
+    @Test
+    void shouldReturnAvailableAsPending() {
+      AvailablePlugin review = createAvailable("scm-review-plugin");
+      when(center.getAvailable()).thenReturn(ImmutableSet.of(review));
+
+      manager.install("scm-review-plugin", false);
+
+      List<AvailablePlugin> available = manager.getAvailable();
+      assertThat(available.get(0).isPending()).isTrue();
+    }
+
   }
 
   @Nested
@@ -275,6 +348,11 @@ class DefaultPluginManagerTest {
       assertThrows(AuthorizationException.class, () -> manager.install("test", false));
     }
 
+    @Test
+    void shouldThrowAuthorizationExceptionsForInstallPendingAndRestart() {
+      assertThrows(AuthorizationException.class, () -> manager.installPendingAndRestart());
+    }
+
   }
 
   private AvailablePlugin createAvailable(String name) {
@@ -296,9 +374,9 @@ class DefaultPluginManagerTest {
   }
 
   private AvailablePlugin createAvailable(PluginInformation information) {
-    AvailablePlugin plugin = mock(AvailablePlugin.class, Answers.RETURNS_DEEP_STUBS);
-    returnInformation(plugin, information);
-    return plugin;
+    AvailablePluginDescriptor descriptor = mock(AvailablePluginDescriptor.class);
+    lenient().when(descriptor.getInformation()).thenReturn(information);
+    return new AvailablePlugin(descriptor);
   }
 
   private void returnInformation(Plugin mockedPlugin, PluginInformation information) {
diff --git a/scm-webapp/src/test/java/sonia/scm/plugin/PluginInstallerTest.java b/scm-webapp/src/test/java/sonia/scm/plugin/PluginInstallerTest.java
index 4e2de333b9..3f918cd4fa 100644
--- a/scm-webapp/src/test/java/sonia/scm/plugin/PluginInstallerTest.java
+++ b/scm-webapp/src/test/java/sonia/scm/plugin/PluginInstallerTest.java
@@ -63,7 +63,8 @@ class PluginInstallerTest {
     PendingPluginInstallation pending = installer.install(gitPlugin);
 
     assertThat(pending).isNotNull();
-    assertThat(pending.getPlugin()).isSameAs(gitPlugin);
+    assertThat(pending.getPlugin().getDescriptor()).isEqualTo(gitPlugin.getDescriptor());
+    assertThat(pending.getPlugin().isPending()).isTrue();
   }
 
   private void mockContent(String content) throws IOException {