Thank you for your post.
Using FileMaker Pro Advanced 16.0.1 under macOS Sierra 10.12.5, I am unable to replicate the issue following your steps.
Does this occur for all files or just a particular file? That is, closing all FileMaker Pro files, create a new file (no fields necessary), and follow your steps, do you still get the same issue?
Do you have any plug-ins or scripts (OnTimer) that may interfere with keyboard entry?
I tried this with a new file and it does work correctly. I have noticed this happening a number of times. It may be related to how long I have been working in the file or how long FileMaker is open. This evening I started up FileMaker and checked the file I was working in this morning, a brand new file and several other projects, all of them are now working correctly.
If this starts again, I'll try and provide more details about what happened. I have seen this happen a number of times since the Pre-release version of 16 came out. So for me it happened in both Pre-release and Pro Advanced 18.104.22.168. This morning when I reported it, it was happening 100% of the time. This evening not at all.
Thank you for looking into this.
The issue seems to come back daily. Usually after I have been working for a period of time. Half hour or longer. It may depend on how often I need to program a Single Step button.
It seems to be all files when connected to a server. I'm having the issue in a hosted file. I opened a local copy of the same file at the same time. In the local copy it works correctly in the hosted the problem is there. This is on the same file, ( one copy hosted, one local ) on the same layout creating the same button.
As soon as I back space and remove the reversed text, type ahead works correctly.
Currently I am running FileMaker Pro Advanced 22.214.171.124 on a MacBook Pro 15 inch 2016, 2.9 Ghz Intel Core i7 with 16 GBytes Ram.
For plugins I have:
2empowerFM Developer Assistant v3.21;3.2100.2.0;Enabled
2empowerFM Parent v2.59;2.5900.2.0;Enabled
I find this a minor annoyance more then anything else.
Thank you for the additional information.
If you disable the two 2empowerFM plug-ins, does the issue still occur?
I've seen this issue which for me was timing dependent. It seems like FileMaker is switching keystrokes at the very beginning if you do it quickly. Try doing it quickly then try doing it very slowly and see if that makes a difference.