WowAce

The issue appeared after update for patch 7.3. The castbar of unitframe would display the cast is cancelled while it is actually still casting if double press action button. Locale: zh-tw.

I have the same Problem man. Im leveling my chaman and i realize cast bar cancels when double press healing wave or healing surge. hope we can fix this. PLS somebody help us T_T

This issue no longer exists to me. It seems to be blizzard's problem or this issue is created by other addon.

Strangely. It seems that this issue only occurs to my toons on one realm but not to the ones on the other realm. Very strange.

Some infos which might be useful to reproduce this problem:

This only occurs on my Resto Shaman for the spells Healing Wave & Healing Surge. This might have to do with unescaped whitespaces in the cast names? My Localization: de

yeah same problem with my Chaman toon at healing wave and healing surge. Same problem with my Main, but im main Dk so dont have much to cast just when i double press Hearthstone or any stone.

Any solution? pls update the addon or fix it !!! T_T

 Same thing happens when I double cast Dalaran Hearthstone, Garrison Hearthstone and Artifact Power Items. (All my toons)

This is still happening. SUF IS up to date.

Also having this issue. Dalaran Hearthstone, Garrison Hearthstone and Prayer of Healing on a priest. 

I created a fix for this issue. You can download it here:

https://www.dropbox.com/s/e7sobordnupjixu/fix_suf_castbar.zip?dl=0

When the player double presses the same spell button, the game will send a UNIT_SPELLCAST_START event for the first press and a UNIT_SPELLCAST_FAILED event for the second press. These events will have the same spellID but will have different castIDs. SUF is only checking the spellID and terminating the cast bar display of the first cast (still in progress), thus deviating from the behavior of the default UI's cast bar.