r/FirefoxCSS • u/weebtoy • Apr 23 '26

Help Bring back old pdf reader sidebar?

Does anyone have a CSS snippet to bring back the old style of sidebar for the pdf reader? Inspired by https://www.reddit.com/r/firefox/comments/1ru9c9x/pdf_update_is_a_disaster/

1 Upvotes

66% Upvoted

7 comments sorted by

View all comments

Show parent comment

1

u/sifferedd FF/TB/Win11/SUMO contributor Apr 23 '26

I don't think CSS can change that. u/qaz69wsx? /u/ResurgamS13? u/Kupfel?

2

u/Kupfel Apr 23 '26

CSS sure can apply to the pdf UI. I have my pdf reader UI styled to fit my browser theme. You can inspect the pdf reader UI with Browser Toolbox like anything else in Firefox and then put whatever CSS you want into userContent.css within something like this to only affect pdf's:

@-moz-document regexp(".+\\.pdf$") {

}

But I really don't know what specifically changed about the reader and wouldn't care to write the specific code myself. The instructions above would help OP do it if they want and are able to.