On some laptops and tablet PCs if you accidentally short this line to Gnd it can cause strange symptoms, current limit or not and even prevent booting in severe cases. PS3 and PS4 the same applies.
I actually found that the Pi Zero V1.1 could actually run on this, charging up an itty bitty LiPo like the ones used in 3D glasses from HDMI power and then activating when triggered from a special remote code or even using a 10F 2.5V supercapacitor.
please note, use a single chip 5 pin charger IC or other limiter if you plan to try this as supercaps/LiPos DO NOT LIKE excess voltage. 2.4V seems to be a sensible hard limit for supercaps and 3.92V for LiPo / 3.25V for LiFePO4.
Note: a Pi Zero can be "juiced" to actually run from HDMI parasitic power if you optimize the code for low usage. I found that by replacing the memory card with one hand selected for lowest power usage it will actually run fine.
Alas NOOBS won't work as it needs 8GB minimum but ArchOS might work or some other distro. Would someone please release PiDSL already thanks! (<256MB)
52mA average would fit most smart TVs.