I can't reproduce this with the current list of top questions here on meta. Can you give more details? Is this after clicking the "N new questions" banner, or is it just after first loading the page?

Loading the front page, clicking on "modified xxx minutes ago" on either Super User or Meta StackExchange. Example on Super User

You are getting a 404 on that link? I don't.

So... what browser, OS and versions are you on?

Hmmm... Wonder if it's something at my location then... I keep getting a blank "404" page... Windows 7 x64, Firefox 49.0.2

What happens when you strip out the ? and everything after it on the URL?

The question loads normally

I can't tell where that ?lastactivity is coming from, but that seems to be the issue here. It isn't on the links I get.

I recorded a GIF, went to edit this question, and I'm getting the Meta 404 error now. Anyways, it seems like it's only for modified questions, not freshly asked questions. I'll upload the GIF somewhere and link it

@oded jmc.sd57.bc.ca/~lbarone/testing.gif

Does this happen if you access over https?

Yes, happens over HTTPS. Do you want to do chat instead of comments?

Sure...

I can repro the link now, just going directly to SU. But - clicking the links works just fine.

I'm going to try in Chrome and IE

OK. What browser are you on? Guessing FF from the theme.

Yes. It works in IE and Chrome, still giving me issues in FF

Latest version of FF?

(not got it installed on this computer, so can't test right now)

I think so... One sec

Disabled all add-ons/extensions/plug-ins/whatever you wanna callit?

Nope... Going to install 50.0.1 first, test, then I'll disable my add ons

OK. Let me know how it goes.

Updating did nto fix it. Going to disable add ons

Disabling all my add ons made the link work correctly (anchor to the right post). I'll re-enable 1-by-1 until I find the culprit. status-norepro?

... User agent changer add on. I forgot I set it last week to act like a Google bot -.-

Sorry to have wasted your time, Oded

No worries - lesson learnt, don't impersonate a bot ;)

Exactly!

We do check for google bot and some things are different

@Oded can't you view a user's agent string in the logs?

@ShadowWizard not if I'm not on my work computer. Also - need to actually go through the logs to do that... and asking someone is faster/easier to do ;)

@Oded heh, fair enough. :)