Weird Window Sizing

I have a weird window sizing using OnlyOffice in Manjaro Linux. Take a look:

Compared to Thunderbird

You might not be able to see what is happening but the top row is massive compared to other apps and the word heading has a drop-down that lists all default print options. Using a different computer but the same monitor all those options are on display. If you compare the title fonts and heights in Thunderbird you will see the difference.