[Serious] Breaks browser styleseets for XML documents

[benbucksch]

Expected Behavior

• The XML, as a tree, expanded (and branches collapsable).
• Stylesheets of the browser and the websites are not affected or destroyed

Current Behavior

• The expected and correct display flashes for a split-second on the screen, then:
• The XML goes completely unstyled, and you see the tags and attributes as plaintext text, without linebreaks
• It appears that there is a stylesheet applied correctly, but then the KeePassXc browser extension comes in and removes it or breaks it.
• The XML is completely unreadable.

Possible Solution

• Don't interfere with browser or site CSS style sheets.
• Scope your own stylesheet properly to avoid class name clashes

Steps to Reproduce (for bugs)

1. Open https://v1.ispdb.net/office365.com in Firefox (This URL returns XML with a Content-Type of "text/xml")

Debug info

KeePassXC - 2.7.7 KeePassXC-Browser - 1.9.1.1 Operating system: Linux Browser: Firefox 128.0 and earlier

[benbucksch]

I had first wrongly blamed the browser https://bugzilla.mozilla.org/show_bug.cgi?id=1906109 before finding out that it's this addon that breaks it.

[varjolintu]

Thanks. Found the reason. The extension does not check the content type before using content scripts. I made a fix where all XML files are ignored with the file extension type or checking the ContentType.

[benbucksch]

Thanks for the super fast response.

Can you use a whitelist (modify only HTML) instead of a blacklist (not XML), to avoid that other file types are broken?

[droidmonkey]

Other file types have style sheets?

[varjolintu]

Other file types have style sheets?

I think this depends on the browser. Some file types are shown inside an internal page that can also allow some styling. At least this seem to happen with Firefox.