Simply edit your global git config named .gitconfig in your $HOME (or %USERPROFILE% on Windows)
You need to replace tru with true or delete core.longpaths altogether from your global settings.
In command line, you can also type:
git config --global unset core.longpaths
cd /path/to/my/repo
git config core.longpaths true
Checks your SourceTree settings though: make sure it is using the System’s Git and not the embedded one.
With Git 2.39 (Q4 2022), documentation on various Boolean GIT_* environment variables have been clarified regarding boolean values:
See commit 819fb68, commit b724df6, commit fd01795, commit 80f0b3f, commit 29491ca (15 Sep 2022) by Junio C Hamano (gitster).
(Merged by Junio C Hamano -- gitster -- in commit a1fdfb0, 10 Oct 2022)
environ: explain Boolean environment variables
Many environment variables use the git_env_bool() API to parse their values, and allow the usual "true/yes/on are true, false/no/off are false.
In addition non-zero numbers are true and zero is false.
An empty string is also false." set of values.
Mark them as such, and consistently say "true" or "false", instead of random mixes of '1', '0', 'yes', 'true', etc.
in their description.