Guard for mentions suggestions list clipped by bottom edge of window

[coxom]

When the mentions popup is near the bottom of the screen it will be moved up so it doesn't get cut.
This correction will only be applied when the property suggestionsPortalHost is not being used.

[DJTB]

Anything I can do to help this through?

[nummi]

I would love to have this feature as well. Thank you for implementing it.

[adityatandon007]

When will this be merged. Needed this badly in one of my projects. Please add this feature and push it in the next release.

[agneym]

Is there any update on this? The PR looks ready.

[jfschwarz]

The proposed implementation does not look like a robust solution to the problem. While it guards against clipping at the bottom edge it will instead cause clipping at the top edge for long suggestions lists.

There are some other undesired behaviors. For example, when looking at the "Advanced options" example on our demo page, it opens the suggestions overlay to the top even though there would be enough space to open it to the bottom.

If you want to help getting this PR through, please add examples to the demo page and propose a more complete solution.