The GUI single-instance lock was previously created through wxSingleInstanceChecker without an explicit Unix path, causing wxWidgets to place .VeraCrypt-lock-$USER directly in the user home directory.
Resolve a private lock directory before constructing wxSingleInstanceChecker. Prefer $XDG_RUNTIME_DIR/VeraCrypt, then $XDG_CACHE_HOME/VeraCrypt, then ~/.cache/VeraCrypt, and keep the previous home-directory behavior only as a final fallback if no XDG location can be used.
Update stale-lock cleanup to remove the lock from the same resolved directory, so false-positive cleanup continues to work after moving the lock out of $HOME.
Fixes https://github.com/veracrypt/VeraCrypt/issues/819
Mounir IDRASSI
2605adcfff