F5 rendering bug - black cube under player

I may for example be in an empty world; nothing around at all: especially not any black cubes. Yet when I do F5 and look at the player form below, a weird black cube appears. Doesn't happen all the time, not in every world? But yeah, it's weird and annoying. It's apparently a common rendering bug...

My own VIDEO showing bug: https://www.youtube.com/watch?v=kJBWJc5oKnw

Is this going to be fixed/does it have a 'fix', but depends on settings or Minecraft version or something; Etc. ? Please help.