Mysterious lines appear different zoom levels

Issue report by WF7A

Product

FileMaker Pro

Version

14, Advanced (Mac)

Operating system version

10.10.3

Description of the issue

Lines/Guides(?) mysteriously appear at the 25%, 50%, 75%, 150% zoom levels, both in Layout and Browse modes, Form and List views.

Steps to reproduce the problem

At 25%, 50%, 75%, and 150% zoom, mysterious lines/guides appear in both Layout and Browse modes, Form and List views, where they didn't before in FMPA v13.x. (If memory serves, this same problem occurred a couple of versions ago and needed a bug fix.)

Expected result

No lines

Actual result

Lines appear. (See attachments.)

Configuration information

16 GB RAM
Only other program open at the time: Firefox web browser

Workaround

None other than not use 25%, 50%, 75%, 150% zoom levels...which is unacceptable in our solutions because users need to be able to resize layouts based on sight ability/disability.

Screenshot