A gargantuan filesize for no reason.

[8E]

AL v 12.1.11 on MacOS, M1.

I have started a brand new file.
I worked for a several days, and today I checked the file size that shows 110 MB. I have never seen this size. It has 40 tracks, some grouping. All MIDI.

I have duplicated the file to see what is the reason.
1. I have deleted each VST instrument. Still I am on 90 MB.
2. I cleared all MIDI data. No change.
3. I have deleted all devices on all tracks. Still 80MB. Just 40 empty MIDI tracks!
4. I have deleted each MIDI track (now completely empty, no MIDI data, no devices) and added the equal number of new empty MIDI tracks. Now my file is 51 KB (Kilobytes!).

What is the reason? It seems that Live doesn't clean up the file, almost like making inside of the file unlimited backups or whatever else.

[8E]

EDIT: Now I have created a new track for each track, copied the complete devices, copied the MIDI data, deleted the old tracks and saved. Now it is 14 MB.

EDIT 2: Sometimes when I wanted to create a new track with the same settings (devices) I simply duplicated the track, and deleted only MIDI. Maybe that was the reason. Now I will only create a brand new track, and copy the devices onto it, not duplicating.