This picture is looking down at the plant from almost directly above it. The flatness of the leaves can clearly be seen. Normally, miner’s lettuce grows so the broad part of the leaf faces the sun. When that happens, viewed from the side, the plant is almost paper thin and sometimes seems to disappear because of it.
That isn’t the case here because it is located in such a way that it gets sunshine and reflected sunshine from almost every direction.
Incidentally, this kind of plant is edible but bitter. The stems and leaves contain a milky ‘latex’. In some places, the latex is dried, which it does readily when it comes in contact with the air, and the dried substance is taken because of a euphoric feeling it bestows. It is also a relaxant and is calming for the nerves if a person can get over the bitterness. It is the latex that makes this plant bitter. Incidentally, domesticated and farmed lettuce also contains the latex, but in much smaller amounts. That is, until the lettuce bolts (goes to seed).