When checkout to a commit without tag, you have a detached HEAD.
git status will show
HEAD detached from 1d9d44eef
Changes not staged for commit:
(use "git add <file>..." to update what will be committed)
(use "git checkout -- <file>..." to discard changes in working directory)
modified: a.c
modified: b.c
no changes added to commit (use "git add" and/or "git commit -a")
In SourceTree, the left Branches area has a HEAD "branch" flag, click it will lead you to the commit. But in Fork, I can not find that commit I have checked out, unless I scroll from the long long commit history.

When checkout to a commit without tag, you have a detached HEAD.
git statuswill showIn SourceTree, the left

Branchesarea has a HEAD "branch" flag, click it will lead you to the commit. But in Fork, I can not find that commit I have checked out, unless I scroll from the long long commit history.