Time Tracking - sessionData is nil after saving a sprite

[Arecher]

Extension: 1.0.2 Aseprite: Aseprite 1.3-rc1-x64

After creating a new file, making some changes, and then saving the sprite, the sessionData sometimes isn't properly saved.

Going back to the Home tab, undoing a change, or switching files using the tabs causes errors on lines 97, 77 or 80. This keeps happening, unless you restart Aseprite completely.

This has happened a few times now. I tried to reproduce it, and I can't find any solid steps. I just kept making new files, making a few changes, and using CTRL+S to save them, and then switching to the home tab. The sessionData being null happened a few times.

I quickly changed my own extension to just return whenever the sessionData isnt valid, but I thought I'd report it just in case.