Mana Flask Not Working in No-Regen Maps

Running in a no-regen map with my mana flask (shown in screenshot below, Chemist's Divine Mana Flask of Warding).

Both times this has occurred, I have had the mana flask equpped before entering the map. I start to clear the map upon entering, and, seemingly at random, the mana flask will stop giving me mana. To make it work again, I need to either un-equip the flask, and then re-equip, or portal out and back into the map. Unfortunately, I haven't managed to figure out what triggers it to stop working.

The mods on the map I was running was Vulnerability, Ele Reflect, and No-Regen. This has occurred twice, on a Plaza Map, and an Ivory Temple map.

I believe this is a problem with the "1" flask slot.

I just had the same problem with a health potion.

Edit: it also only seems to be with resource recovery flasks, also seems to affect the flask for a time after its been in the "1" slot

Could you possibly have a finger on a modifier key such as CTRL,ALT,SHIFT, the Windows Key, or even TAB while trying to press [1] for your first flask slot?

iirc, this has been reported as a problem for some.

Even if not, I sometimes experience a problem with the Windows key becoming locked in POE (like the game had not handled or passed on a key-up event). This will cause many other keypresses to be interpreted as Windows commands outside of the game process.

If it uses charges and doesn't recover, it's a lag-related hp/mp pool snapshotting(dunno if that's really the right term or the whole explanation) issue. Using a Seething flask would fix the issue, as it re-aligns server and client side hp/mp pools.