Does the same happen for you on the official portable version? https://gitlab.com/api/v4/projects/44042130/packages/generic/librewolf/128.0.3-1/librewolf-128.0.3-1-windows-x86_64-portable.zip
If not, try contacting the maintainer on the Portableapps.com forum.
Seems like it's similar to https://reddit.adminforge.de/r/LibreWolf/comments/1f4ush4/