As the title states:
Windows 10
x64
Build 15060
No Anti-virus (other than Windows Defender)
March 20th nightly portable - No issues (and all previous builds are fine)
March 21st nightly portable - Won't start at all
The crash on startup when the list of recent files and projects was not completely empty was fixed (https://github.com/mean00/avidemux2/commit/c255a13781b81394be7df1d5a2936e0d27647149) by Mean in git master today.
Yes
I can confirm that v 23rd March works fine.