I went through 68 example sentences for 額 and only 4 of them referred to a picture frame. That’s a very small amount.
The usage was about 50-50 between forehead/brow and amount (or a variation of amount, like total).
I feel like the meaning of the vocab should either be changed or these synonyms added officially, because I feel like it’s a little misleading.
I actually just assumed prior to reading the example sentences that picture frame / frame / picture was it’s only meaning as a singular kanji, and that assumption would’ve lead to some serious confusion while reading, I imagine…