Ok I didn't get the screenshot, but I acquired the "Tavish Elexir" (silly spelling may apply) in the 1st map of the scenario and kept it onto the 2nd map.
In the second map I "re-found" it in my inventory and was like "Oh, I still have this"... I noticed I could not sell it to a shop, (It would not show up in the shop window, only the equipment window).
Also in the Equipment window I could "Use" it, giving Relias a permanent state of the "Growth" spell...
If anyone is happening upon a Tavish Elexir, can you check if it was a "Once in a million" bug? 
Sincerely
~ Kongdej
