This is a weird one. I'm using FMPA 16.02 to edit a hosted file.
I have been doing a lot of refactoring on a layout after making a new T.O. and rebasing an existing layout on the new T.O. This has involved a lot of manual editing of calculations, e.g. Hide conditions, etc. I have attached a little screen capture showing the erroneous erasure happening. This problem has survived a program closing/opening (FM itself, not just the file). I have NOT been able to replicate it in a new file, however. It is highly repeatable in this one file in question, though.
I noticed after a bit that sometimes I would lose a leading word when replacing the table name in the calculation. This is in the case of a clause that has multiple logical tests connected with "OR" or "AND". Here's an example calculation:
Get( WindowMode ) = 1
or cur_PROJ TALENT::show_Photo = 0
or cur_PROJ TALENT::NotAvail = 0
In this case I was replacing "cur_Proj Talent" table name with "Lists_Anchor". I would use the option-Delete and option-backspace to delete the existing table name. I would then start typing the new name and the calculation auto-complete pop-over would show up with suggestions. I would type enough to get close and then hit the Tab key to accept the current selection. But when I hit Tab it would erase the word "OR" and the start of the line.
If I had two spaces between the "OR" and the table name I was replacing, then it would NOT erase the leading word. You can see this in the video - I have added a 2nd space between the "OR" and the table name before doing a replace.
In the video I replace the instance in the first line without any incident. At around the 4 second mark I start editing the 2nd line in the calculation, which is when the odd bits start. At around the 7 second mark you can see as I delete the table name and start typing the new one, then at the 9 second mark the new table name I want is shown and highlighted. The only thing I do after it is highlighted is to hit Tab - I didn't use the mouse for anything, nor use option-Delete nor cmd-Delete to remove anything - just hit the Tab key. At which point it deletes the leading word "OR" from the start of the line. The 3rd line goes off without a hitch because I added (for demonstration and testing purposes only) a second space between the words.
I have made some light attempts to recreate this in another file but haven't been able to.