Regarding preventing this from happening again, any pulls that are accepted will automatically change the character sheets the next time you open the game. It won't change any data, unless there is a Sheet Worker Script (which the PTA sheet does not), but any changes may hide old values because a different name is being used. For example, looking at the changes made, "move_name1a" was replaced with "movename1a", which means "move_name1a" is still stored in the Attributes tab but is not displayed anywhere on the sheet. The only way to use a custom sheet but ensure nothing was changed without your say-so would be to get a Pro subscription, choose "Custom" as the character sheet instead of PTA, and copy the code from github into your game settings (there are three tabs in game settings, corresponding to the htm, css, and json files in github. That way, even if the character sheet on github changes, you will still use the copy you made for your custom sheet.