Hi! Sir! Please look at the following picture, this is certainly not normal:

And the normal is:

Very humble question, but it's always a problem.

At the beginning, there was no question. But after a period of time, it appeared.
1.8 and 1.9 I have not tested, but I think it should not be normal.

If I delete MalisisDoor, there is no problem.

I think this is a rendering bug, please take a look for this.
Thanks!

I've seen a similar issue. Thanks for a hint, I'm going to try some new angles to look from, as it is definitely not limited to beacon.

It seems like when certain blocks are near the doors, z-fighting occurs. Very odd, I must say.

Ok, to me, it seems to be randomly occuring z-fighting.
Try restarting your client, you will likely have no issues with it for a short while.

@Ordinastie I know what bug is !!!!!!
Beacon !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

After a long test ( Only use MalisisDoors Mod without any other mods ), I found the following questions:

If I use Beacon (If there's a beacon near the door):

Rendering bugggggggggg !!!

If I break Beacon (If there's no beacon near the door):

Everything is normal !!!!!!!!!!!!!!!!!!!!!!!

Oh !!! The BUG is, Beacon and MalisisDoors don't know why the conflict!

By default, faces are only rendered one way. Somehow the beacon changes that behavior without restoring it.
However, 1.7.10 is way too old to bother fixing it, sorry.
On a brigther note, that bug doesn't happen in 1.9.4 :)
Thanks for reporting (and investigating) anyway.