website somtimes unusable in Internet Explorer 11

[Dieter Van Uytvanck]

On 21 and 22 June 2018, the clarin.eu website turned out to be unusable with IE 11 on windows. The site showed up in the mobile rendering (including the hamburger menu) but this menu was not responding when clicking. With other browsers (edge, chrome, FF) there was no problem.

On 4 July the issue could no longer be reproduced. I think some erroneous HTML code in one of the news items (the summary showing up in the flexslider widget) might have been the cause but this would need closer investigation. Reporting it now mainly to have a reference to this issue if it pops up again.

[Dieter Van Uytvanck]

Problem is occuring again (report 13 September 2018). Hendrik can you take a look?

[Dieter Van Uytvanck]

Feedback from Hendrik:

Hi Dieter, HTML validation reports some errors: ​https://validator.w3.org/nu/?doc=https%3A%2F%2Fwww.clarin.eu%2F
I think they are not severe, but you never know, if IE parsers get a hickup...

[mail@hendrikschmeer.de]

By chance I googled the problem and found that a missing compatibility header could cause the problem in IE-11, who defaults to compatibility-mode in intranets:

<meta http-equiv="X-UA-Compatible" content="IE=edge">

I cannot find that element in the sourcecode of the page.

This is being proposed here:

​https://stackoverflow.com/questions/22302106/pages-does-not-render-properly-in-ie-11-when-using-the-bootsrapv3-0-0-theme

If this cannot be checked otherwise before, I would start next week in trying to reproduce the problem on my machine, when I continue work.

[mail@hendrikschmeer.de]

Inserting the meta tag into the HTML fixes the display of the stored HTML source code (last week) in IE 11, running in virtual box.

However, the bug did not show (this time) up while loading the page directly from ​https://clarin.eu in IE 11 running in a virtual box.
The bug reporter (​Griet.Depoorter@ivdnt.org) tells that the bug currently has disappeared when loading the page on her system.

Proposed solution, inserting meta tag at the right place:
<meta http-equiv="X-UA-Compatible" content="IE=edge">

This would require overriding the default html.tpl.php file by the theme (this file doesn't exist, yet).

[mail@hendrikschmeer.de]

Found an alternative solution without adding the html.tpl.php to the theme. Submitted pull request.

[André Moreira]

We do have ​page.tpl.php wouldn't that be the right place to insert the meta tag?

[mail@hendrikschmeer.de]

Replying to André Moreira:
no, that does not add anything to the HEAD section

[André Moreira]

Replying to mail@…:

Found an alternative solution without adding the html.tpl.php to the theme. Submitted pull request.

Looks good to me.

I have one question: are we sure that inserting the meta tag into the HTML fixes the issue? From Dieter's comment 9 I understand that the problem disappeared on its own before we had the chance to test it. Is that so?

[mail@hendrikschmeer.de]

I saved the HTML source code last week and loaded it using IE 11 on virtual box today, showing the bug! Indeed, loading the live page was fine.

Adding the meta tag to the saved source fixed the issue.
So we know how to prevent IE from switching to compatibility mode, but not what is causing it to do so...

[André Moreira]

Great, thank you for the explanation! I agree it should be fixed now.

Feel free to close the ticket.

[André Moreira]

Deployed on https://dev-www.clarin.eu/