The mangrove schematics I've made have had a long time changing and getting better since the first few I made. Attached are my favorites, updated to have 3 blocks of roots and hanging propagules.

I personally prefer these to the vanilla ones- much easier to cut down, while also resembling the mangroves I know from real life (Hard to believe, but I touch grass!). So excuse my hubris, that I feel that I'm more intimately familiar with mangroves being a wildlife nerd from Florida than the Mojang developers in Sweden. No shade- they're better programmers than me though >.>



To get the effect I did in the pics with Worldpainter:

• offset by y= -1
  
• spawns under water & on land
• Replace underground blocks: if existing block is air

or just use the .layer file I attached. Then apply at or above your water level is minus 1 (default is 62, so at or above 61 for me).

Note that these aren't the ones from the other tree packs. I will update them at a later date as of me writing this. This is just for others' convenience since I just built/redid these.