By default, the Minecraft client has a hard-coded delay of 300 ms (6 ticks) between breaking blocks, unless your tools, enchantments, and potion effects are strong enough to completely bypass it, as per the following wiki article: https://minecraft.fandom.com/wiki/Breaking#Instant_breaking

This mod simply sets that delay to 0, allowing you to break multiple blocks much faster than before, without affecting the time it takes to break a single block.

GitHub: https://github.com/CovenantTurtle/MiningCooldownFix

Modrinth: https://modrinth.com/mod/mining-cooldown-fix

CREDITS:

• IDontEvenKnow, Kochu (especially for leaving instructions on how he did it), and anyone else involved in making this mod for older versions of the game, as chronicled in these threads:

https://www.minecraftforum.net/forums/mapping-and-modding-java-edition/minecraft-mods/1276978-1-6-2-click-mining-fix-fix-speed-up-all-mining
https://www.minecraftforum.net/forums/mapping-and-modding-java-edition/minecraft-mods/1293388-snapshots-1-8-8-forge-click-mining-fix-fix-remove

• lStewieAl of Fallout: New Vegas fame for making a functional .jar version of this mod for Minecraft 1.18.1, which I used as a basis for this Fabric mod

• The helpful people in the Fabric Discord server for helping me learn how to properly use mixins in Fabric

Mining Cooldown Fix