Device: Xiaomi Redmi 5
OS version: Android 8.1.0 OPM1
App version: 5.6.2 build 422 sdk 7.3.3.49
Mode: network disabled for the app
Two updates later I encountered a situation that the search in editing .txt files stopped working: I was able to fill the fields but the button seemed to be off, with no visual feedback. I decided to wait for a new update.
The recent update broke the editing completely — I was not able to make any changes in the sheet though my keyboard (google one) appeared on the screen. The letters I wrote appeared in suggestions bar on the keyboard but not in the sheet, and upon saving the file I got it unaffected. So I made 4-star rating with description of the mess.
Now it is seemed that the editing is working good. Maybe the issue was in the Google keyboard, but the that-time nonworking search/replace suggests against this assumption. I will remove my 4-star rating now, because the issue is seemed to be resolved and mended somehow.