My server is using MC 1.7.10, and there's some bugs present (which were fixed in newer versions). So I decided to grab Vincent Lee's Bugfix Mod (which was never released on CurseForge) and maintain its fork.
Fixes are (as described by original mod's author):
- Experience orbs spawn correctly
- Chat opacity works again
- Chickens lured by everything they can breed with
- Hearts flash the damage taken
- Hearts blink when regenerating
- Tools enchanted with Unbreaking don't reappear randomly
- Snowballs/eggs/enderpearls knockback players in SMP again
- Items don't bounce in locked hoppers nor on stairs
- Village blacksmiths spawn an anvil in their shop (disabled by default)
- Boats do not desync!
The most annoying thing was the boats desynchronisation bug (MC-2931).
Also I fixed a bug preventing players from sleeping in beds placed above y=128 (MC-3599).
Other stuff was not tested.