--- a/devtools/client/webconsole/webconsole-ui.js
+++ b/devtools/client/webconsole/webconsole-ui.js
@@ -144,26 +144,47 @@ class WebConsoleUI {
    */
   init() {
     if (this._initializer) {
       return this._initializer;
     }
 
     this._initializer = (async () => {
       this._initUI();
-      // Bug 1605763: It's important to call _attachTargets once the UI is initialized, as
-      // TargetCommand.startListening will start fetching additional targets
-      // and may overload the Browser Console.
-      await this._attachTargets();
+
+      if (this.isBrowserConsole) {
+        // Bug 1605763:
+        // TargetCommand.startListening will start fetching additional targets
+        // and may overload the Browser Console with loads of targets and resources.
+        // We can call it from here, as `_attachTargets` is called after the UI is initialized.
+        // Bug 1642599:
+        // TargetCommand.startListening has to be called before:
+        // - `_attachTargets`, in order to set TargetCommand.watcherFront which is used by ResourceWatcher.watchResources.
+        // - `ConsoleCommands`, in order to set TargetCommand.targetFront which is wrapped by hud.currentTarget
+        await this.hud.commands.targetCommand.startListening();
+      }
 
       this._consoleCommands = new ConsoleCommands({
         commands: this.hud.commands,
       });
 
       await this.wrapper.init();
+
+      // Bug 1605763: It's important to call _attachTargets once the UI is initialized, as
+      // it may overload the Browser Console with many updates.
+      // It is also important to do it only after the wrapper is initialized,
+      // otherwise its `store` will be null while we already call a few dispatch methods
+      // from onResourceAvailable
+      await this._attachTargets();
+
+      // `_attachTargets` will process resources and throttle some actions
+      // Wait for these actions to be dispatched before reporting that the
+      // console is initialized. Otherwise `showToolbox` will resolve before
+      // all already existing console messages are displayed.
+      await this.wrapper.waitAsyncDispatches();
     })();
 
     return this._initializer;
   }
 
   destroy() {
     if (!this.hud) {
       return;
@@ -326,27 +347,16 @@ class WebConsoleUI {
    *
    * @private
    * @return object
    *         A promise object that is resolved/reject based on the proxies connections.
    */
   async _attachTargets() {
     this.additionalProxies = new Map();
 
-    if (this.isBrowserConsole) {
-      // Bug 1605763:
-      // TargetCommand.startListening will start fetching additional targets
-      // and may overload the Browser Console with loads of targets and resources.
-      // We can call it from here, as `_attchTargets` is called after the UI is initialized.
-      // Bug 1642599:
-      // TargetCommand.startListening ought to be called before watching for resources,
-      // in order to set TargetCommand.watcherFront which is used by ResourceCommand.watchResources.
-      await this.hud.commands.targetCommand.startListening();
-    }
-
     // Listen for all target types, including:
     // - frames, in order to get the parent process target
     // which is considered as a frame rather than a process.
     // - workers, for similar reason. When we open a toolbox
     // for just a worker, the top level target is a worker target.
     // - processes, as we want to spawn additional proxies for them.
     await this.hud.commands.targetCommand.watchTargets(
       this.hud.commands.targetCommand.ALL_TYPES,