Rewrite.
a) use QMap instead of QHash because of
b) don't keep every client but only (temporarily) the relevant ones (typically << 10) and therefore
c) don't leak
d) the bloody QHash:operator[] should yell a compiler "#warning WRONG!" ;-P
e) i raised the anim time from 200 -> 300, matter of personal taste though (it's esp. about fade out, because there's also another client appearing -animatedly- pot. sucking cpu anyway, thus blocking updates for a short while)

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:: I vote for an exceptional backport to branch despite it's a big patch.
:: It's only a tiny effect & little code and whatever regression i wrote into it - i cannot be worse ;-P
:: (patch is for branch, i'd just copy the file over to master then. ws should be ok - hopefully...)

Yes. See QtDebug include in the first version :-)