Library update deletes additional files in sketch folders

Hi, I´m a newbie in Arduino´s world and I don't know if is normal, but recently I've updated some Libraries in IDE and some "backup" files that I store in the same sketch folder has disappeared, they had the *.txt extension because I used to copy and paste my sketches in text files to avoid opening a lot of IDEs. My *.ino files remain untouched. Any help would be really appreciated because I've been working in a project and those files were my only backups

Start by reproducing a library update in Arduino IDE 1.x with .txt backup files stored alongside an .ino sketch. Investigate which update step removes the additional files; done means library updates leave unrelated files in the sketch folder untouched.

Written by the indexing model from the issue text.