Primo v tom clanku, na ktery odkazujete, se pise:
We'll have the spec API implemented soon in Firefox nightlies, but in the meantime, many of the basic functions translate directly from our own variant to the spec version, so you shouldn't need to wait to take advantage of text in Canvas-using apps."
Bug s tim spojeny je vyreseny. A tady je k tomu blog post primo od autora implementace.
Kazdopadne to uz odbihame od puvodni myslenky, a to ze nefunkcnost Bespinu v prohlizecich imho neni chyba, ale vlastnost. Bylo by samozrejme fajn, kdyby fungoval vsude, ale jak uz jsem rekl, to je na vyvojarich prohlizecu, nikoliv na autorech Bespinu.