The QB is a law unto itself. Try typing a phrase in inverted commas. The first word will always appear in lower case even though you you have typed upper. This is because it recognises the punctuation mark as a letter, therefore anything that follows must be in lower case.
A while back the Ed did a poll, the result of which was to get rid of this. We thought it would come in with the new format, but alas, no.
I feel certain that AB does Not have a Spell Checker built into its Questions & Answers programmes. It depends on what Browser you are using and if it has been programmed for a Spell Checker.
Say what Browser you are using and someone will give you advice on the issue concerned.