I made a resource pack with a rainbow border that appears when mining a block, but I noticed that the last texture called "destroy_stage_9.png", where the border should appear full or complete was never displayed on screen (or if it was maybe it was for less than a tick or so, possibly when the block was already mined), because even when mining obsidian or other slow blocks was never seen at all.

I'm almost certain that this is a bug, and I don't know if the border I'm making should stop at "destroy_stage_8.png" and leave "destroy_stage_9.png" transparent for now or perhaps wait for an update with this bug fixed (1.17.2 or maybe 1.18). But I believe that this happens too to some older Minecraft versions. Thanks in advance and have a nice day