Topic: How on earth do I clean this glass!

[chopin-liszt]

If sodium bicarbonate fails, I have a go with vinegar - which should dissolve limescale.
I can't see bleach doing much unless it's against organic muck - which you should have dealt with already.

[Lustrousstone]

Whatever you do isn't going to "hurt" because if it goes white it's not going to show on the outside, unlike the muck. More patience and soaking and swirling might do it.