I double-clicked layer name, and wanted to type “front arm”.
But the viewer become fullscreen when i typed “f”, and a “insert text” dialog popped when i typed “t”.
So I got a “ron arm”, and a full-screen viewer, and a “insert text” dialog…
Oh thanks for reporting this! I’ll release a fix this week for this. In the meantime you could remove the F key as a shortcut for the Full Screen command from Edit > Keyboard Shortcuts… menu: