Solar template: CSS "error"

[CiotBSD]

I use the template Solar on the billboard.

Into the Linux forum, a category tag is displayed, but actually, it's not possible to "understand" what it's wrote into this tag. The text within is “invisible”, unreadable!

See the screenshot:

[CiotBSD]

In fact, it's not a problem specifically to the forum Linux, it's on all!

[grahamperrin]

https://www.google.com/search?q=Solar+site%3Acommunity.nodebb.org%2Fcategory%2F10%2Fnodebb-themes&udm=14 finds Solar at https://community.nodebb.org/category/10/nodebb-themes however a logged-in search finds nothing that's obviously relevant.

[grahamperrin]

Similarly, with the Yeti skin I get missing texts in the Powered by area:

Also with Yeti, https://billboard.bsd.cafe/unread failed to show the name of at least one category, OpenBSD. I wonder whether the issue will be reproducible with the default (no skin).