The problem

I was trying to merge branches using the "Squash and merge" option in GitHub Desktop, expecting all commits from the target branch to be compressed into a single commit. However, the operation performed a regular merge instead, preserving all individual commit history.

Release version

3.3.5

Operating system

windows 11

Steps to reproduce the behavior

Steps to reproduce:

1. Open GitHub Desktop and navigate to a repository
2. Switch to a branch (e.g., UncivCN)
3. Click the "Choose a branch to merge into UncivCN" button
4. Select a branch to merge (e.g., pr/13930) which has multiple commits (34 commits in my case)
5. Click the "Squash and merge" button
6. Observe the result in the commit history

Expected behavior:
All commits from the merged branch should be compressed into a single commit. For example, merging a branch with 34 commits should result in only 1 new commit being
added to the target branch.

Actual behavior:
A regular merge was performed instead. All 34 commits from the branch were preserved in the history, creating a merge commit that retains the full commit history rather
than squashing them

Log files

No response

Screenshots

No response

Additional context

No response