Yes, you should definatly backup before updating anything in Joomla. Updates will override any custom CSS work you've done to an extension or template that isn't in a custom CSS file.
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e courteous to staff and members that volunteer their time helping you E
ssential Tool - FireBug N
ever assume I know what version you're talking about
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earch the forum for a solution first I
nclude a link to the problem M
ark your resolved issues as [SOLVED] O
nly PM moderators if they request it first N
o...