HTML input text cannot select text using mouse

Question

I have a HTML page with input text elements and textarea elements. Text typed into these elements can be selected with the mouse cursor. Clicking anywhere on the text value places cursor in that location.

In some cases, the mouse functions stop working. Cannot use the mouse to place cursor or to highlight/select text.

So far, I have been able to eliminate javascript interaction as a possible cause. The misbehaving elements are deep inside div/span hierarchy (5-6 deep), moving the same element outside the div nesting, fixes the mouse functions.

Anyone has ideas what could be the cause?

Thanks

Abhi