Sequence: a previous crash leaves a crash database in /tmp, the next start shows a consent dialog nobody answers, adb never sees a device; deleting the database restores a normal boot
Android

The Android emulator would not boot: a crash-consent dialog from the previous run was waiting for a click

adb devices stayed empty. The log said ‘Showing crashdialog to get consent’. Deleting /tmp/android-$USER/emu-crash-*.db fixed it.