Can confirm but this is a duplicate/addition to https://bugs.mojang.com/browse/MC-277200 & https://bugs.mojang.com/browse/MC-277086
Can't reproduce (I harvested half the forest lol)
Can confirm
Can confirm
Can confirm but the bug only occurs and changes everything to blue text if you quit the world when the "Wither" text in the boss bar is blue right in that moment. If you quit when the text is white, everything is normal.
Also applies for the text in the escape menu, the settings and every UI element of the main menu (Singleplayer, Multiplayer, Realms)
Can confirm
Can confirm
Can confirm
Can confirm. It's one dark line for each the "displayname" and the "numberformat" command argument
When updating the display name ("displayname" argument), the right dark line appears and when updating the number format style ("numberformat styled" argument(s)), the left dark line appears. So they are kind of separate from another
Can confirm
Can confirm
Can confirm but you need to be really fast with turning & hitting