For the record, one can enable/disable such thumbnail creation (and look for a tooltip with the description;)) with Tools—Preferences—Appearance—Hyperlinks—Store map preview. Also, grep for create_thumbnail_on_save in the source code. Auto-export on save sounds like a big feature request. I.e. each map should have some sort of local options on how to save it (export format and maybe some export preferences).
I think I can confirm this bug too. Not as drastically as on the screenshot, but yes, tops and bottoms are truncated, so e.g. dots of "i" and bottom parts of "g" are disappeared during editing. That is why I always prefer to edit in Long Node mode. I see this behaviour on stable (1.0.1), unstable (1.1.0 Beta 2) and commit cc87d4a4 (the latest working commit for Linux at this time). Java versions 8 and 11, Arch Linux.
I think this "bug" could be closed as wontfix or so: both stable and unstable releases can be compiled on Java 8 only and run on Java 8 and 11 (from the list of the Arch Linux supported Java versions). The latest commit can be compiled and run with Java 17, but it has a bug with stack overflow while editing long nodes. Basically, this is not a bug, but a feature request about latest Java support. And with the latest versions (21, 22) there is another problem - Security Manager is deprecated.
This problem is not related to Java 17 and commit a1cfa85e. The latest good commit is cc87d4a4. The next two commits — bb964c15 and 832707b2 — can't be compiled: BUILD FAILED /home/korshikov/stuff/Projects/aur-freemind-git/src/code/freemind/build.xml:50: taskdef class org.jibx.binding.ant.CompileTask cannot be found using the classloader AntClassLoader[] I'm not a Java man, sorry if these two could easily be fixed and tested. And, finally, 095dc4e6 is compiled successfully and the bug in question...