Fix setting focus in field when 'ctrl+f' when find panel is collapsed

[boltex]

Only if the find panel is not opened !

When it's collapsed the focus cannot reliably be put into it when unfolding it. So while unfolding just gather the user input with a regular inputBox

...and fill the find-panel search input box with it for next search with 'Enter' or 'F3'.

on the other hand, If already expanded, just do the usual.

[boltex]

Instead, set a flag up to mean that it needs focus, and let the panel detect when unfolding/appearing, to then check if that flag is set (if so, set focus in field and clear the flag)