Here's a list of abilities that counter stealth, just for everyone's reference (shamelessly taken from heroesofthestorm.gamepedia):
Tassadar's trait, "Oracle", enables him to reveal a large area surrounding him for 5 seconds.
Chromie's level 1 talent, "Timewalker's Pursuit", reveals a targeted area for 2 seconds and any heroes revealed for additional 4 seconds.
Gall's level 1 talent, "Eye of Kilrogg", places an eye that reveals a targeted area for 45 seconds.
Lieutenant Morales, Malfurion and Raynor's level 1 talent, "Scouting Drone", places a drone that reveals a targeted area for 45 seconds.
Rexxar's level 1 talent, "Flare", reveals a targeted area for 20 seconds.
Brightwing's level 4 talent, "Peekaboo!", adds an additional effect to her "Phase Shift", revealing the area for 6 seconds.
Kharazim's level 4 talent, "Air Ally", places an air ally that reveals a targeted area for 40 seconds.
Lunara's level 4 talent, "Skybound Wisp", adds an additional effect to her "Wisp" ability, causing the wisp to reveal the area for 4 seconds after dying.
Medivh's level 4 talent, "Dust of Appearance", reveals surrounding enemy heroes for 10 seconds.
Murky's level 7 talent, "Clairvoyance", reveals a targeted area for 10 seconds and any heroes revealed for additional 4 seconds. This will be removed with Murky's rework
Rehgar's level 7 talent, "Farsight", reveals a targeted area for 10 seconds and any heroes revealed for additional 4 seconds.