I face a strange issue with the android libraries, using
com.sun.mail:android-mail:1.6.5
com.sun.mail:android-activation:1.6.5

The crash occurs in MailcapCommandMap.java line 601, where a new instance of multipart_mixed is created (also happens with other classes extending handler_base)

If i create a release build, OR enable minify for the debug build, OR run it on Android 10 or lower, the error does not occur.

Stacktrace:
java.lang.VerifyError: Rejecting class com.sun.mail.handlers.text_plain that attempts to sub-type erroneous class com.sun.mail.handlers.handler_base

Caused by: java.lang.VerifyError: Verifier rejected class com.sun.mail.handlers.handler_base: java.awt.datatransfer.DataFlavor[] com.sun.mail.handlers.handler_base.getTransferDataFlavors() failed to verify: java.awt.datatransfer.DataFlavor[] com.sun.mail.handlers.handler_base.getTransferDataFlavors(): [0x4] can't resolve returned type 'Unresolved Reference: java.awt.datatransfer.DataFlavor[]' or 'Reference: javax.activation.ActivationDataFlavor[]'

To reproduce, put this code in an Android project and debug it on Android 11 (device or emulator)

ClassLoader classLoader = getClassLoader();
Class cl = classLoader.loadClass("com.sun.mail.handlers.multipart_mixed");
Object multipartMixedObject = cl.newInstance();

I am unsure, if this is an issue with the library, or rather something on Android OS side, in any case, it's not working.
(as our release builds are still working, this is not a really important issue, but one i would like to solve sometime regardless)