I have a variety of house plants I pick up from a nursery that has "indoor plants" and "outdoor plants" areas. We can't communicate well due to different languages, but I understand that some plants do well with some direct sunlight each day and others I should try to avoid that.
I have a large unobstructed east-facing window in my "solarium" (bathroom) so I've been experimenting.
I've found that for example my coleus cuttings get droopy when their roots are underdeveloped and they get direct sunlight, and as soon as I pull them back out of the light they "re-inflate". So that's temporary dehydration and doesn't seem to have permanent damage.
But for chronic problems or permanent damage due to sunlight, is the problem generally due to dehydration that's bad enough to do permanent tissue damage, or is the light also doing something more directly to the leaves? Can there be too much photosynthesis for example? Free radical production perhaps? Is there such a thing as "plant sunburn"?
Related:
- Haworthia do not like direct sun, especially when kept as a houseplant...
- These plants all like humidity so I regularly spray them (plus my apartment tends to be on the humid side), and they all like indirect sunlight
- Ignoring plants that love or require direct sunlight, my understanding is that generally plants don't like it too much (leading to sunburn) and rather prefer bright indirect or filtered light