SourceTree doesn't recognise wildcards in Git LFS tracking

When tracking file with Git LFS we use a wildcard pattern for case insensitivity such as:

*.[pP][nN][gG] filter=lfs diff=lfs merge=lfs -text

This allows us to keep our .gitattributes smaller while still catching all the weird permutations that different software packages use for file extensions. However, SourceTree doesn't recognise these patterns so when we go to add new *.png files it warns users that the files are large and should be tracked in Git LFS.

The work around is to track all variations of file extension cases in use individually and bloat the .gitattributes, making it harder to manage and defeating the point of what we're trying to do.

Is it possible for SourceTree to support better pattern matching for Git LFS file type tracking?