COMEWhy Android names a file manager during COME installation
Android's source-permission prompt can name the app that opened the APK. That may be a file manager even when a browser originally downloaded it.
Trace the handoff
The browser saves a file, and another application may open it later. Android evaluates the installation source at that opening step. Compare the prompt's app name with the action you just took instead of assuming every prompt must name the browser.
Limit permission scope
Only consider permission for the source you intentionally used and trust. Enabling unrelated apps does not repair a file or make it authentic. If the requesting app is unexpected, cancel and return to the completed download in a known interface.
Review after the task
Once installation is finished, you can review source-installation permissions in Android settings. Menu names vary, and managed devices may restrict changes. Play Protect should remain enabled regardless of which source opens the APK.
A useful next step
Use one recognised route from completed download to Android's installer, without switching through unknown helper apps.
Related: What to do if Android warns about a COME APK