BLUE TONGUE SKINKS

Hello everyone. My halmahera blue-tongued skink Mars has been doing this very weird thing where he just goes up to the left side of his enclosure and rubs up against the glass for over a minute straight, usually multiple times a day. He never does this anywhere else, only in this one specific spot. I tried covering that side of the glass with cardboard but that didn't seem to stop him, so he's definitely not trying to get to the nearby table. I'm just concerned, honestly. I recorded a video of him doing this and posted it onto Youtube.

https://youtu.be/4bUno_EuiNM

Looks like normal glass surfing behaviour, nothing to be worried about. Males will often do this ad nauseam around mating season, often combined with pacing the edges of the cage. Skinks go through phases of this, you can try and take him out when he does it as he simply may be bored/wants to explore.