Due to an influx of spam, we have had to approve account registrations. Please write an email to support@manjaro.org, with your username, if you want to get access faster. Sorry for the inconvenience.
Firefox CSD will draw a top frame border with 15px
The Vertex-Maia-Dark with CSD firefox, the top frame border will be 15px.
I use Vertex-Maia-Dark, and fix it modifying /usr/share/themes/Vertex-Maia-Dark/metacity-1/metacity-theme-3.xml
Adding <distance name="button_height" value="0" /> to frame_geometry with name="border" and name="borderless"