I realize this is a topic which has been discussed to infinity, and there are some great posts to be found on here regarding 404 problems.I read this post, and while very informative it did not answer my specific question so forgive me for opening yet another 404 question.Ok, so the general consensus is that 404 errors generally does not harm your site regardless of the number...I get that!However, I know Google places a great deal of emphasis on user-experience. Now when I get messages like this from Google, I start to get a bit panicky...Googlebot for smartphones identified a significant increase in the  number of URLs on http://www.example.com/ that return a 404 (not  found) error. If these pages exist on your desktop site, showing an  error for mobile users can be a bad user experience. This  misconfiguration can also prevent Google from showing the correct page  in mobile search results. If these URLs don't exist, no action is  necessary.Now my primary concern here is the fact that they say this can be bad for user experience...or am I interpreting this incorrectly?I should also mention that the primary reason behind the 404 errors is because I get these weird social details at the end of each of my urls like this one which adds my twitter handle to the end of the url for some bizarre reason:tag/tutorials/news@example.comShould I be concerned about the above?I realise the message says if the URL does not exist you don't have to do anything, well it doesn't exist, but it also does in the fact that it is a page on my site, just without the twitter handle at the end?Confused...head spinning...should I be worried?
Google message about 404 errors, should I be worried?
seo;google;google search console;404
Having something appended to your URLs in search console is usually either a malformed link on your site (in this case your twitter link probably), or Googlebot being dumb and interpreting a JavaScript string like var=tag/tutorials/news@example.com; as something that the JS could use as a link, maybe.   The first would effect users, but not the second.   I tend to fix them all, just because I hate errors in the reports, but fixing an error that users don't see shouldn't be needed.