Yordles and their glamour (general wonderings from the new comic)
As I understood it until now, 'glamour' was a magic that hid Yordle's true appearance from baseline humans, while those attuned to magic, or other worldly abilities, can see through it. It's mentioned in certain character lores that they are seen differently or outright ignored by the populace (see Tristana and Kled). It was until now seemingly just an innate magic they have.
So in the new Jinx and Ziggs comic, it is shown that Ziggs and Heimer appear just as short humans to people. This is a result of their glamour. Yet they seem to be able to suddenly control it and Heimer mentions he conjured it as a charm. Meaning not only it is a spell but one Heimer made (the scientist can do charms... he's a true genius). Ziggs mentioned it's his 'weird glamour thingy' and how he might not use it, showing they can have control over it.
This revelation is actually very disappointing in how Yordles exist. I thought (and liked) the idea that their glamour was an innate magic they just have. The Yordles might not even know how it works or if it even exists, as Tristana says "I’m a young slip of a girl!", meaning she doesn't know how she appears to baseline humans because she doesn't see that, she sees herself as herself.
The idea that all these Yordles that have left Bandle City have this charm seems misplaced too, does Veigar have it? Why would he bother? If a small evil Yordle was running around, people would know about it. In Poppy's comic she was basically ignored yet was the only Yordle there, people would surely be shocked at the sight, she has the charm but where/when did she get it? Kled no doubt left Bandle City hundreds of years ago as he was at the formation of Noxus, yet he apparently has the charm making him appear as a cranky old man (fitting).
I'm also keeping in mind, Eduard Santangelo, the explorer who wrote about the Vastaya said at the end of his journal "Those illusive fae creatures of legend, the yordles." meaning they are meant to be near a myth, not just wandering around in plain sight.
TL;DR: Glamour is inconsistent and I'm thinking about it too much.