The HTML markup of the search button has been changed at some point, I think. Ajax Search Lite (and I assume Pro as well) no longer HTML validates, but throws the following error:
“Element div not allowed as child of element button in this context.”
For a more complete error description and maybe a hint of a solution, see https://validator.w3.org/nu/?doc=https%3A%2F%2Foldrup.net%2Fajax-search-lite%2F
(I assume this error was introduced in relation to the nice accessibility improvements, tab-index).
I’ll gladly test any beta containing a fix – just say so 🙂
Bjarne