I think a new dynamic UI bug, and it sounds like Benjy saw something similar today.

▶ ./pants test src/python/pants/backend/python/lint/docformatter/rules_integration_test.py -- -k type_stubs
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12:21:21.38 [WARN] Completed: Run tests - src/python/pants/backend/python/lint/docformatter/rules_in
𐄂 src/python/pants/backend/python/lint/docformatter/rules_integration_test.py:integration failed.

Going from 120 pixels wide to 121 pixels wide in my terminal fixed it..?

I'm not sure exactly what's going on there - are you saying that if the terminal window is less than 121 pixels wide, artifacts are left on the screen?

Artifacts are left on the screen, and the result is not streamed. I didn’t get the test result, only the title “WARN”

we do expect artifacts to be left on the screen if you resize the terminal while pants is running. I don't think there's anything that can in principle be done about this, short of writing a really sophisticated ncurses-aware library from scratch