Since the beginning of Season 14, the immunity bubble that would appear surrounding the Glyph upgrader after killing the Pit Guardian in The Pit, was no longer spawning. This created some friction amongst players, as surrounding enemies no longer de-spawned when the player completed the bar to spawn the Pit Guardian. Players sometimes got caught losing health or even dying while trying to upgrade their Glyphs.
Earlier today there was a blue post on the forums from Community Manager Lyricana confirming that "The pit bubble will be returning in an upcoming patch" with no date or other information. When today's patch was released, players were surprised with the return of the pit bubble!