I had my AST VGA from 1993 turned on earlier to watch a couple of episodes of Beyond Belief Fact or Fiction in a true-to-life 1990's manner. Anywho I got up and saw this when I looked down:

https://m.imgur.com/gallery/HAs4d

That's a view from outside the top cooling vents towards the very back. I'm assuming that's the base of the CRT correct?

Should it glow like that after only perhaps an hour and a half of use? The glow disappeared immediately when the display was disengaged but that's kind of scary. I've worked on newer CRTs with the casings off and never noticed any glow or light of any type, but I guess I've also never done it in the dark though I would think such a glow would certainly be noticeable in lighter conditions.

Do I have a serious issue here or is it just part of how these older CRTs function? I remember someone here not to long ago mentioned they had once seen an IBM 5150s neck begin to glow red hot and I must wonder if I'm observing the exact same phenomenon here. If that's heat and not just light passing and refracting through glass that I'm seeing I'm assuming that isn't safe at all.