We always get this Logger error messages on startup and we use a snapshot version of log4j2 which will probably take a long time until it's stable.

We already use slf4j as a Logger interface, so switching to another underlying logger should not be that complicated. Most stuff should be compatible.
We currently use slf4j-2.0.0. This requires at least tinylog 2.4

https://tinylog.org/v2/download/#slf4j

What needs to be changed?

1. Replace log4j2 with tinylog and the bindings.
2. Investigate if we still need our custom Logging Plugins or if they need to be converted https://tinylog.org/v2/extending/
3. Remove log4j stuff also from jpackage/jlink
4. Test if it works on all platforms