1416184 - @import in userContent.css ignored for websites

Status: UNCONFIRMED

(Core :: CSS Parsing and Computation, defect, P3)

Description

[Sergey Vlasov]

Attachment: hide_all.css

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:58.0) Gecko/20100101 Firefox/58.0
Build ID: 20171109220104

Steps to reproduce:

Download attached hide_all.css and place next to userContent.css (create, if doesn't exists) under <profile>/chrome/. At the top of userContent.css add this rule:

@import "hide_all.css";

and restart Firefox.


Actual results:

Only Firefox internal pages are affected, e.g. "Preferences", "Add-ons" etc. Websites are unaffected, e.g. https://google.com


Expected results:

Any page content should be blank white, e.g. https://google.com

Workaround: instead of using @import rule, embed the content of hide_all.css directly into userContent.css.

Comment 1

[corben.dallas]

I'm experiencing the same issue with FireFox 57 when electrolysis is enabled.
Another workaround is to disable e10s by setting browser.tabs.remote.autostart.2 to false.