Apologies if this is not the place to post bug reports, but I cannot find anywhere more suitable.
A web page that I was working on last night that was error-free in the editor, and which was published (and works perfectly fine) this morning now shows a number of errors in the editor. All relate to page elements that the editor claims are not valid selectors. Note that I have not made any changes to the page in question since last night.
I have tried closing my browser, clearing the cache etc. but the issue remains. Previewing the page reveals that functionality related to the page elements that the editor is complaining about is indeed broken, which is super annoying.
Anyone else experiencing this sort of issue?
EDIT
Here are a couple of images to clarify what I am talking about - the first is a screenshot from the page in question, and the second is from the code:
And just to reiterate, all of the code worked perfectly last night.