I'll join in because I also have a similar problem. I added a button to the app that changes the icon. When I click it, the app closes, the icon changes and theoretically there's no problem. However: shortcuts stop working, it doesn't start automatically after pressing debug. You have to manually start from the shortcut, and the errors I get are:

My main class: MainActivity
My alias name: MainActivityDefault

In the folder containing the main class I also have an empty class as in the shortcut name

When starting debug:

Activity class {com.myproject.myapp/com.myproject.myapp.MainActivityDefault} does not exist

When starting the shortcut:

Unable to launch. tag=WorkspaceItemInfo(id=-1 type=DEEPSHORTCUT container=# com.android.launcher3.logger.LauncherAtom$ContainerInfo@1a1bf6a targetComponent=ComponentInfo{com.myproject.myapp/com.myproject.myapp.MainActivityDefault} screen=-1 cell(-1,-1) span(1,1) minSpan(1,1) rank=0 user=UserHandle{0} title=Pokaż na mapie) intent=Intent { act=android.intent.action.MAIN cat=[com.android.launcher3.DEEP_SHORTCUT] flg=0x10200000 pkg=com.myproject.myapp cmp=com.myproject.myapp/.MainActivityDefault bnds=[359,640][1115,836] (has extras) }
                                                                                                    android.content.ActivityNotFoundException: Shortcut could not be started
                                                                                                        at android.content.pm.LauncherApps.startShortcut(LauncherApps.java:1556)
                                                                                                        at android.content.pm.LauncherApps.startShortcut(LauncherApps.java:1521)
                                                                                                        at com.android.launcher3.BaseActivity.startShortcut(SourceFile:1)
                                                                                                        at com.android.launcher3.BaseDraggingActivity.startShortcutIntentSafely(SourceFile:8)
                                                                                                        at com.android.launcher3.BaseDraggingActivity.startActivitySafely(SourceFile:9)
                                                                                                        at com.android.launcher3.Launcher.startActivitySafely(SourceFile:6)
                                                                                                        at com.android.launcher3.uioverrides.QuickstepLauncher.startActivitySafely(SourceFile:2)
                                                                                                        at com.android.launcher3.touch.ItemClickHandler.startAppShortcutOrInfoActivity(SourceFile:14)
                                                                                                        at com.android.launcher3.touch.ItemClickHandler.onClickAppShortcut(SourceFile:8)
                                                                                                        at com.android.launcher3.touch.ItemClickHandler.onClick(SourceFile:6)
                                                                                                        at com.android.launcher3.touch.ItemClickHandler.b(Unknown Source:0)
                                                                                                        at O0.f.onClick(Unknown Source:0)
                                                                                                        at com.android.launcher3.popup.PopupContainerWithArrow.lambda$getItemClickListener$0(SourceFile:1)
                                                                                                        at com.android.launcher3.popup.PopupContainerWithArrow.d(Unknown Source:0)
                                                                                                        at F0.e.onClick(Unknown Source:2)
                                                                                                        at android.view.View.performClick(View.java:7441)
                                                                                                        at com.android.launcher3.shortcuts.DeepShortcutTextView.performClick(SourceFile:3)
                                                                                                        at android.view.View.performClickInternal(View.java:7418)
                                                                                                        at android.view.View.access$3700(View.java:835)
                                                                                                        at android.view.View$PerformClick.run(View.java:28676)
                                                                                                        at android.os.Handler.handleCallback(Handler.java:938)
                                                                                                        at android.os.Handler.dispatchMessage(Handler.java:99)
                                                                                                        at android.os.Looper.loopOnce(Looper.java:201)
                                                                                                        at android.os.Looper.loop(Looper.java:288)
                                                                                                        at android.app.ActivityThread.main(ActivityThread.java:7839)
                                                                                                        at java.lang.reflect.Method.invoke(Native Method)
                                                                                                        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
                                                                                                        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)