Sporadically broken HTML formatting since at least 3.5.0

[stavr666]

NetBox version

v3.5.1

Python version

3.10

Steps to Reproduce

Spontaneously observed behavior:

1. Open any list
2. Click to any object
3. Press "Go back" (or ALT+←) in browser

Expected Behavior

List will be rendered as usual.

Observed Behavior

Loaded only part of page, without sidebar, with empty head tag:

[DanSheps]

Thank you for opening a bug report. I was unable to reproduce the reported behavior on NetBox v3.5.2 (Also not able to reproduce on 3.5.1). Please re-confirm the reported behavior on the current stable release and adjust your post above as necessary. Remember to provide detailed steps that someone else can follow using a clean installation of NetBox to reproduce the issue. Remember to include the steps taken to create any initial objects or other data.

[arthanson]

I have seen this also from time-to-time recently. I thought it was just some glitch when I was debugging stuff so didn't bother to track it down, but I have seen this several times. On a Mac using chrome browser, not sure if that has anything to do with it.

[abhi1693]

I don't think it's a bug with netbox. Just how browsers load the css and js. When you click back, if the styling is not loaded this happens and I have seen it on other sites too.

[DanSheps]

Yeah, I tried it with Chrome on both my prod and the demo and no joy. It could also be browser specific.

I think I may have seen it before too, and when I encountered it I thought at the time it was just a glitch with the HTMX request.

[stavr666]

Please re-confirm the reported behavior on the current stable release

It's totally reproduceable in 3.5.0, 3.5.1, 3.5.2. I encountered it dozen time my own production installation (3.5.0, 3.5.1) and at least once in every 3 versions on your Demo-site, during my check of some conceptions before generating other reports there.

But I agree with @abhi1693 that it's look like browser-related (3 different Chromium-based), because it never reproduceable on repeat (forward-back buttons).

[DanSheps]

Honestly, the lack of HTML in the screenshot makes me think it is the browser replaying a HTMX request, which results in only a partial HTML being sent and it glitching. (You only get the table, not anything else like the nav menu)

If we had a consistent way to reproduce this, we could maybe track it down better.

[kkthxbye-code]

Probably similar to this:

bigskysoftware/htmx#1201

I can reliably recreate it by going to the device list, order the table by a column, closing the tab and then hitting ctrl+shift+t in chrome (re-open closed tab). This only renders the table, without css.

Anyway, there's some context if anyone wants to look into it. There's some suggestions in the linked issue.

[DanSheps]

Looks like we might just need to use the cache-busting params.

[jeremystretch]

This seems like it can be addressed by setting the Vary: HX-Request response header as described here.