Edge Browser Monaco editor cursor error

[Bigbrd]

There were numerous incidences where on the Monaco code editor, the user would click at the end of a line and the cursor was not placed where they clicked. These only repro-ed on Edge Browser.

[alexdima]

We do feature detection for hit testing, in the following order: document.caretRangeFromPoint, document.caretPositionFromPoint and finally document.body.createTextRange.

It looks like Edge decided to implement document.caretRangeFromPoint, which it didn't support before, but it implemented it in a broken way.

[alexdima]

Edge's implementation is not necessarily broken, it is a matter of interpretation. Edge sometimes returns a token's <span> as the hit container and sometimes a token's text node, while Chrome always returns a token's text node