While you're holding the spear, you can't break blocks only the attack animation appears. The video explains the situation more clearly.
Environment
It affects when you break blocks and the block break animation doesn't occur.
MC-304066
You cannot break blocks while holding spears
Resolved
Works As Intended
0
Thank you for your report!
However, this issue is Working as Intended.
The report you have submitted is working as intended: see the 25w41a changelog:
Please note, that mechanics of the game may change between updates.
Things such as graphics, sounds, world creation, biomes, redstone, villagers, and animals may not work the same in current versions.
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