Data loss when painting on template

[lpechacek]

While this is somewhat unusual use case, this really happened. Paint on template function rewrites data when the draft images share a common name on the disk.

Steps to reproduce:

1. In the mobile interface, click on Add template... in the Paint on template button menu multiple times without moving the map view port.
2. Paint in both templates
3. Save file, close, reopen

Actual result: Drawing in the bottom templates is lost.

Expected result: OO Mapper should warn that there are colliding draft templates, or name the files in the permanent storage in a way that they don't overwrite each other.

Screencast.From.2026-06-14.09-12-17.mp4