Windows 10; Audacity 2.4.2
I’m sure I’m doing something wrong, but when I try to select and label two regions while audacity is playing, something appears to go wrong.
To reproduce, generate 30 seconds of silence. Press the space bar to begin playing. Now, while the clip is playing, press the following characters in sequence: “[”, “]”, Ctrl-“B”, “abc”, then enter, then: “[”, “]”, Ctrl-“B”, “def”, then enter. What I am hoping for is to mark and label two regions, one labelled “abc”, the second labelled “def”.
Audacity creates the first label just fine. And the next “[” sets the next left boundary just fine, but the following “]” acts as though I had just typed Ctrl-“B” before it: it creates a point label at the point where the left boundary was set then treats the “]” as data for the label. (I never get to the Ctrl-“B” or the “def”, etc.).
Works not so well for me with Audacity 2.4.2 on Widows 10 Version 1909 (OS Build 18363.1139):
Yes, That’s exactly what it “looks like”. So I am merrily watching the cursor march rightward across the screen, when I press “]” and voila, a point label suddenly and magically appears and a label is created with the single character “]”.
I don’t see what else you can do? 
Now, all I have to do is figure out why my Multi-Tool is popping up! 
But I’ll save that for another day…