difficult sentence

[adel87]

dear all in this sentence Mozilla has some interesting tricks up its sleeve, and while you're waiting for the new versions of Firefox, you might as well check out Mozilla's projects page to see some of the features planned for Firefox's future. what is the meaning of tricks up it sleeve thank you

[euncu]

Source:sleeve - Idioms - by the Free Dictionary, Thesaurus and Encyclopedia.

have something up one's sleeve and have an ace up one's sleeve
Fig. to have a secret or surprise plan or solution (to a problem). (Alludes to cheating at cards by having a card hidden in one's sleeve.)
-- I've got something up my sleeve, and it should solve all your problems.
--The manager has an ace up her sleeve. She'll surprise us with it later.