[Nextcloud] Default theme shows gray text on gray background

[cm-schl]

Describe the bug
The default theme used by SnappyMail when integrated into Nextcloud seems to use the theme color of Nextcloud for mouse over links. This is a problem if in Nextcloud the theme color was set to gray (like #DADBDC) because the background of the active menu is also gray:

To Reproduce
Steps to reproduce the behavior:
In Nextcloud Settings -> System Settings -> Design set the color #DADBDC as color to use for your Nextcloud. Then enter in SnappyMail and hover over a link.

Additional context
I know #629 is work in progress and should arrive but as @hampoelz is working on it I would like to ask if maybe in this cases the link text could be shown as black (just a workaround).

[cm-schl]

Thanks! 🙂