Harmony Endpoint Firefox browser plugin corrupting XML files

[Ben_Dunkley]

I'm seeing a slightly odd issue with the harmony browser plugin in Firefox when viewing XML documents.

For example, trying to look at SAML metadata XML files (e.g. https://login.microsoftonline.com/common/FederationMetadata/2007-06/FederationMetadata.xml)

In testing across 3-4 different client devices, both Chrome and Edge rendered the document correctly while the Harmony plugin is active, whereas in Firefox, if the Harmony plugin is active all the XML tags get stripped out resulting in a mostly unreadable document.

There is no change when disabling all plugins/extensions apart from Harmony, but the issue goes away as soon as the Harmony plugin is disabled (by launching a private window).

Both the 'view source' and 'inspect' options do appear as expected.

(We're seeing this in current versions of both Firefox 128 ESR and 133, and with plugin version 990.100.834 and endpoint version e88.32).

Any thoughts?

Or just log it with TAC?

Thanks,

Ben

[Ben_Dunkley]

Also - the correct page rendering does show up for a very brief time (~ quarter of a second or so), before being replaced by the unreadable version.

[PhoneBoy]

TAC is probably going to need to investigate.

[Ben_Dunkley]

Fair enough - that'll be a task for next year then!

Thanks 🙂

[wizard_pl]

Hi PhoneBoy,

Just wanted to confirm this issue is still occurring on a current setup — same symptom as originally described (blank page for XML/WSDL content in Firefox, content only visible via View Page Source, works fine in Chrome/Edge, and correct rendering returns in a private window with the extension not permitted there).

Environment where it reproduces:

OS: Microsoft Windows 11 Enterprise, Version 10.0.26200, Build 26200 (corporate managed endpoint)
Harmony Web Protection extension version: 990.106.104
Firefox versions tested: 140.13.0 (ESR) and 153.0.4 — both affected

Interestingly, this problem does not occur on other one computer with the same builds; I don't know what it depends on.