Just a heads up - More of a change than a bug.
On this wiki page https://hcwiki.cityofheroes.dev/wiki/Cce_(Slash_Command) it lists Binds and Macros for costume changes. i.e. /bind NUMPAD0 "emote none$$cce 0 ccBackFlip"
However, with the animation changes in the April 20th patch none$$cce appears to have broken and the emote does not play, just the costume changes after about 10 seconds.
I tried removing the "none" from the line, because the wiki says this is for an animation cancel and animations were changed, resulting in /bind NUMPAD0 "emote $$ cce 0 ccBackFlip" the change and emote work however you get a syntax error in your system messages.
The command /bind NUMPAD0 cce 0 ccBackFlip with no quotes and without emote none$$ appears to function normally. The animation plays and there is no syntax error.
If you use the CCE binds from that wiki page, you may need to update your binds accordingly.