The border lines of tables become transparent.

[nova tartan]

The lines of tables disappeared after upgrade to mediawiki 1.39.

[hazy kettle]

link?

[nova tartan]

Example: https://wiki.slimelab.net/w/index.php?title=奶奶的拐杖&oldid=5657

[hazy kettle]

desktop mode skin is Citizen?

[nova tartan]

Medik

[hazy kettle]

I'm on mobile and honestly struggle to change looks
first time I opened I got the page in mobile, seemingly Minerva, and tables seemed to be ok
maybe something was changed in CSS, and why do you link version from history?

[nova tartan]

Nothing important.

Yes, the tables look fine on Minerva. So I think it's Medik's issue?

[hazy kettle]

probably yeah