Something(a plugin) is causing a strange memory corruption in your sim session.
Your log is filled with the following string:
"AIRCRAFT/X-AVIATION/SAAB 340A/PASSENGER VARIANT/LIVERIES/LDJ-WAGGA WAGGA VH-SBA/"
This eventually builds up into a log clogging repeating mess that is probably overwriting various bits of memory in the sim that will eventually lead to a weird behaviour or a crash.
I don't know for sure what's causing this but because the string has been converted to ALL CAPS I can say that it's not Gizmo.
Gizmo does not perform a caps transformation on the data, there's no need to do so at any point, it only makes life harder if you support all three OS in your source code and design. (Linux specifically is case sensitive..)
You can see Gizmo logs the same data here:
0:02:26.124 G64: core: Livery Changed: Name:(liveries) Folder:(Aircraft/X-Aviation/Saab 340A/Passenger Variant/liveries/LDJ-Wagga Wagga VH-SBA/)
My advice is to try disabling FlyWithLua.... fly a session, inspect your Log.txt for any ALL CAPS data about the livery selection.
I base this on the fact that it's running unknown scripts and shares close memory alignment with Gizmo because of the use of Lua.
It also shows some activity in the Log file between the time when Gizmo logs the livery data (cleanly) and the first signs of the glitch appear in the Log.
The other plugins showing activity during this window are GroundTraffic, AOS (doing a weather update) and X-RAAS and they seem unlikely to be inspecting the livery data.
If disabling FWL doesn't work I'd try disabling:
X-Plane 11/Resources/plugins/SAM/
X-Plane 11/Resources/plugins/SkunkCraftsUpdater/
Hope that helps..
Ben