When no-HUD view is active (default toggle key: F1) and resource packs are reloaded via F3+T, the loading screen that appears will be at half resolution, covering only 1/4 of the screen.
Attached is a sequence of the screen as it progresses in normal view (expected) and as it progresses in no-HUD view.
Thank you for your report!
We're actually already tracking this issue in MC-144588, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature in the future to see if the issue has already been reported.
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