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List of issues
#1410 ability of adding new tags in the SystemClass of a SWFAuthor: 
GameHunter
GameHunterDate created:
Type: feature
Visibility: Everybody
Assigned to:
State: closed 
As far as I know, it's possible to add new animations in Sprites and new sounds in Sounds,
but they are becoming useless if they cannot be named. And there comes the SystemClass
tags that show exactly the names of these.
You can edit SymbolClass tag - you find it in others section. Just press edit, and then
add new item on the end.
State: new→upgraded
State: upgraded→closed