cache the current session

[poyribn]

Checklist

• I made sure that there are no existing issues - open or closed - to which I could contribute my information.
• I made sure that there are no existing discussions - open or closed - to which I could contribute my information.
• I have read the FAQs inside the app (Menu -> About -> FAQs) and my problem isn't listed.
• I have taken the time to fill in all the required details. I understand that the request will be dismissed otherwise.
• This issue contains only one feature request.
• I have read and understood the contribution guidelines.

Feature description

Fossify Paint should save a full snapshot of the current session into its cache, so that the drawing doesn't disappear when i use other apps and later re‑open Paint from the recent apps list.

Why do you want this feature?

Without this feature, the drawing disappears when Android clears working memeory for the 1 or 2 most recently used apps.
With this feature, Paint can restore the session because a backup is stored outside RAM.

Additional information

No response