My users are getting the following in IE 11 (Discourse version v1.9.0.beta2 +218) on Windows 10: [image] I don’t see this on meta or https://try.discourse.org/ in IE 11 on the same browser, so I thought that maybe a plugin is causing the problem. When I enter into safe mode and disable everything, I still get the error message. Any additional troubleshooting suggestions to help determine what might be happening?

Not sure if this is helpful / or you already know, but to disable compatibility mode, go to tools > compatibility mode settings and uncheck the display intranet site in compatibility view setting / or remove the discourse site from the compatibility sites list. [image]

Here is what I’m getting: [image] window.ie undefined window.history { length: 1 } window.history.pushState undefined navigator.userAgent.indexOf("Android") -1 If I run the same process on meta, I get results similar to yours. It “feels” like a mandatory login + SSO problem. Do you know of any other similar sites you folks host that we could see if they’re having the same issue on IE 11? [image] mpalmer: please provide a publicly-accessible URL Because of the type of data we have, we’re not able to make our site publicly accessible. But in the past I’ve PM’d folks on the team with temporary credentials if that would work.

If window.history.pushState is undefined, there’s your problem – if that’s false, you’ll get told your browser is too old. I’m not an expert on this part of things, but my understanding is that that is something that is provided by the browser (as part of the browser’s support for HTML5), not by Discourse, so it’s a bit mystifying that it would be undefined in an otherwise modern browser. Where things get super weird is: [image] wesochuck: If I run the same process on meta, I get results similar to yours. That suggests to me that there’s something, somewhere in your site that is undefining that key. If you were running any freaky plugins, I’d definitely be giving them some epic side eye, but as you’re apparently sticking to the straight and narrow, I guess that isn’t likely. On the other hand, a binary search of the impacted plugins would only involve a max of five rebuilds, so it might be worthwhile giving it a try (I’d start with a no-plugins rebuild, just to validate that the problem is in one of them, and then go splitsies thereafter). If that doesn’t provide any diagnostically useful results, or a few rebuilds are just totally out of the question, I’m going to have to defer to someone else on the @team who has ninja skills in JavaScript debugging to give some guidance, whether that’s some further stuff you can try in the IE11 console, or perhaps just “temp creds please, I need to rummage around”.

Look at the warning at the top: The attached page targets document mode 7. Some console APIs and features may not be available. Something is making IE run in compatibility mode. Search Stackoverflow, there are some questions that seem relevant.

This might be relevant to Discourse: [Luke Woodward] IE11 window.history.pushState "Object doesn't support property or method 'pushState' javascript, html, internet-explorer-11, history answered by Luke Woodward on 04:57PM - 11 Apr 15 UTC

[image] Hector: Look at the warning at the top: The attached page targets document mode 7. Some console APIs and features may not be available. Good catch. I brushed straight over that. Most of the stuff I can find on that error talk about fixing it by setting X-UA-Compatible (via http-equiv meta tag, usually), but as far as I can see meta doesn’t do that, either, so it presumably isn’t a panacea, nor generally necessary for Discourse. I’ve found some posts talking about compatibility modes being set in a list; is it possible the browsers you’re all using have been configured to have your site on an IE compatibility mode list? I’m thinking this might be doable via, say, site-wide group policies or something similar. I can rule that out, at least, if you PM me some temp creds – if I can load the page OK, it’s a browser config issue.

[image] mpalmer: but as far as I can see meta doesn’t do that, either Meta isn’t on an intranet. Maybe this is the problem: [image] wesochuck: We’re running a docker based install on Ubuntu on a local virtual machine in case that makes any difference.

Really great detective work that is almost certainly it; on your local network ie11 is forcing old browser compatibility mode.

We should just add the header back

Nah, I object to serving this header 100% of the time to everyone to fix the .01% of the time this is an issue.

I’m disturbed by the idea that IE11 would assume, prima facie, that anything “local” (same subnet? on any RFC1918 address?) would require compatibility mode.

Browser too old message when "compatibility mode" is forced in IE 11

Product Support

simon July 4, 2017, 4:20am 18

Meta isn’t on an intranet. Maybe this is the problem:

Topic		Replies	Views
Problems clicking topic links in IE11 Product Support	9	2751	January 4, 2019
Site does not work on Internet Explorer 11 after recent update Product Support	2	820	August 11, 2019
IE 10: Blank page is showing rather not supported message Bug	5	1148	May 6, 2019
Infinite loop when mentioning in IE11 Product Support	5	1138	May 1, 2020
Discourse is ending support for Internet Explorer 11 (IE11) on June 1, 2020 Announcements	5	8731	June 14, 2022

Browser too old message when "compatibility mode" is forced in IE 11

Related topics