doesn't look like one,i don't see the wall restoring itself either.

Here

also you should have kept the save private,allot of newbies are going to vote it down (and a few immature people)

The thermite didn't go through the wall.

If you look at the ctype of the lava that flows out, you'll see that most of it is molten glass.
Basically, the heat from the thermite melted the glass, and the molten glass at the edges flowed off of the block.
The glass in between never went anywhere; it just melted and resolidified.
(well, some of it might have turned into BGLA, but...)

Or something like that.
Either way, it's not a glitch.

Yeah, like the guy above me said, it's mainly molten glass that comes out, and the glass that dosn't flow out solidifies - making the wall appear to regenerate itself