BUG: Insert/Overwrite becomes inoperable in pancake editing after opening second timeline.
Insert/Overwrite works when you open a sequence from the Source Monitor in the timeline for pancake-style editing—for the first sequence you're cutting into. After opening a second sequence, it stops working.
1. Open a sequence in the Source Monitor (mine had multicam footage, it may not matter).
2. Click the Source Monitor wrench icon and choose Open in Timeline.
3. Open another sequence to cut into.
4. Do some inserts/overwrites from sequence A to B.
5. Open a second sequence to cut into.
6. Close the first target sequence.
7. Attempt inserts/overwrites.
At this point I'd expect insert/overwrite to keep working, but if this bug has reproduced for you, you won't be able to unless you close the source sequence and reopen it.
Probability: Medium, the editor has to like pancake editing, know how to do it, and be cutting into several sequences instead of just one.
Impact: Medium, the editor has to take a second to reopen the source sequence and find his place again, then he has to go write a bug report.
Pr 13.1.2, Mac