Why is Android Studio's emulator tool window unavailable for some apps?

Question

In some of my (flutter) applications, I can run the Android emulator in a tool window. But in most cases, I cannot; the emulator window does not appear, and there is no View > Tool Windows > Emulator menu entry (as well as other missing tool windows, including Profiler, App Inspection, Build Variants, Dart Analysis, and Device File Explorer).

Comparing the settings for projects that do and do not show the emulator tool window, I'm seeing no differences. Both have the same Android SDK (11.0) and SDK settings (same build tools, platform tools, etc.). Same emulator, of course, as well as same setting to launch the emulator in a tool window.

All the apps work fine in the Android Studio emulator, it's just a difference of whether or not I can run the emulator in a tool window.

Is this a bug or is there some other setting I need to change? (I'll be happy to add additional settings info, if necessary.)

I can recreate the issue simply by creating a new flutter project. I have had the issue for awhile now, but my current settings are:

Android Studio Arctic Fox | 2020.3.1 Patch 1 Build #AI-203.7717.56.2031.7621141, built on August 7, 2021 Runtime version: 11.0.10+0-b96-7249189 amd64 VM: OpenJDK 64-Bit Server VM by Oracle Corporation Windows 10 10.0 GC: G1 Young Generation, G1 Old Generation Memory: 1280M Cores: 4 Registry: ide.intellij.laf.enable.animation=true, external.system.auto.import.disabled=true, ide.balloon.shadow.size=0 Non-Bundled Plugins: com.mallowigi.idea, Dart, org.jetbrains.kotlin, io.flutter

Solution

After additional searching, I found the solution posted here with screenshots seems to solve my issue. Basically, you click File, Project Structure ... Select Modules in Project Settings and then the + button for your project. Add the Android module and click OK.