This is not a duplicate!
MC-273107 was about the color of the tipped arrow entity not having a colored tip (because it's only a normal arrow entity with potion data).
This bug report is about the lack of effect particles coming off of tipped arrows when a custom_color is set in the potion_contents component of the tipped_arrow item. This is a bug introduced by the new data components format for items and should be addressed, since there is now no way to set a custom particle color on arrows.
Affects the current snapshot, 1.21 pre-release 4
You're right, tryashtar; together those reports cover the whole issue of the attack cooldown indicator.
I don't imagine any of these will get fixed because of Combat Update v2.
Note that the Combat Test Snapshot V5 fixes this issue by making projectiles grant 0 invulnerability frames. If this feature is introduced in a major release snapshot, we'll have the fix.
In 1.13 pre-5.
We can't know that for sure until a dev confirms it with that resolution. I'm rather hoping this isn't intended.
This is still in 1.13 pre-release 1
Still in the latest snapshot, 18w16a
This still affects 18w16a.
This still affects the most recent snapshot, 18w14b.
If anyone is wondering, yes, this is still in 18w11a.
The vast majority of sheep are white-wool... you're telling me you found a pack of sheep and no two/three sheep had the same wool color? And you couldn't find dye to recolor the sheep?
This still affects 1.12.2. Very annoying for my game.
Still in 1.12.2
Still affects 1.12.2, although the Minecraft Wiki at the very least treats this as intended behavior; there was .5s after raising shield before it was effective in early 1.9 snapshots, but this was reduced to .25s before 1.9's release. If the delay is longer than this, and isn't due to some form of lag, then it's a definitely a bug.
But even if it is intended, it shouldn't exist
And still in 1.12.2
Oh and still affects 1.12.1.
Confirmed for release 1.12.1
Still present in 1.12.1
There is a partial fix for this bug/feature request in 1.21. Item components specifying potion contents contain both a "show_particles" and "show_icon" field. Setting the former to false will default to hiding the icon as well, but it can be overridden with show_icon:true. Other places where effects can be defined (such as the /effect command) do not have this feature yet, so it's still not completely "resolved" if we consider this a bug.