Certain blocks will squeeze their textures when facing in different directions. It probably has something to do with all the recent changes to models. The blocks that I saw doing it were buttons, fences, and fence gates. There may be more, though I don't think there are.
MC-91943
Certain blocks squeeze texture into small space (depends on direction)
Resolved
Duplicate
0
Thank you for your report.
However, your ticket has been resolved as a duplicate.
This issue has been linked to the original bugreport: MC-91715. You can find or add further information on that report.
Please search before reporting any bugs, as it's likely that one exists already.