This has come up a couple times now and I can’t seem to find any information regarding it and it seems to be sporadic at best.
A user is in Opportunity/Quote Entry with Quote # 456789 with 4 lines. They highlight line 2 and hit delete. The line deletes, but Opportunity/Quote Entry is now on Quote # 123456.
If you can duplicate it (even if not 100% of the time), turn on tracing to get some more insight. I don’t think you need to enable any details (“Full Dataset”, Track Changes…"etc …). Just check what methods are called, and their parameters.
One more thing. Is the quote it jumps to loaded in the form? (this sample snippit shows just one record “loaded”)