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kotlinlang

What version of studio are you on? This is a known bug with how studio is resolving dependencies for lint, when there is a transitive dependency which offers a newer version of activity implementing that interface, see:
<https://issuetracker.google.com/issues/152245564>
<https://issuetracker.google.com/issues/146585040>

I'm on AS 3.6.2, and am depending on "androidx.appcompat:appcompat:1.1.0" across all modules.

Upgrading to <https://developer.android.com/jetpack/androidx/releases/appcompat#1.2.0-beta01|1.2.0-beta01> doesn't seem to solve it either.