When we run a spellcheck, the dialog box has a button for Options, which is not disabled or dimmed, but, when the usual manual process is begun and finished, the dialog goes away, so the button cannot be selected. This is contraconventional behavior for an enabled button. One solution is to change the completion dialog, which says "The spellcheck is complete" and has only the OK button, so that it has two buttons, with the OK button still the default; the other button could be "Return to dialog".
My hardware description is a guess.
This is design team material.
Ideally we would like to get rid of that “The spellcheck is complete” dialog box, which is mostly useless, and replace it with an infobar inside the main Spellcheck dialog.
I have suggested in bug 79312 that the OK button should not close the spellcheck dialog but should return you to it.
We're replacing our use of the 'ux-advise' component with a keyword:
Component -> LibreOffice
Add Keyword: needsUXEval
With a clean UI in mind I wouldn't place access to options in this dialog; Tools > Options > Language > Writing Aids is sufficient. But as bug 79312 is fixed this issue is solved as well (WFM), and there is no urgent need to change the dialog.