Doesn't work with LibreOffice on macOS

[moeenio]

Bug description
When dragging a LibreOffice window over the Multrin window, nothing happens. Other apps work.

To Reproduce
Launch Multrin
Open any document in LibreOffice
Try to add the LibreOffice window to the Multrin window - nothing happens.

Details:

• Operating System: macOS 10.11.6
• Multrin version: 1.2.2
• Last known working Multrin version: /
• Scaling (in percentage, if present): /