Leaf minor? miner? Not good at spelling that, but take the leaves off and burn them. Those are the larvae making those trails. Not fun!

Might be, the weather has been kind of erratic lately. I've moved them into the shade and sprayed them with neem oil in case of mites and yes the cup has a several drain holes lol

Leaf miners. Usually not too much of a problem except appearance although some think the trails open the leaf for potential diseases. Usually by the time you see those trails the wee larva have already left (21 to 28 days from hatch to pupate) although I have on rare occasions seen them boring through the leaf and squished them. There are numerous predators of these larva as well adults and there is little you can do about the larva in the leaf, although there are some reports that some products (Neem or Spinosad) seem to stop the wee buggers. The problem is they are well protected inside the leaf. The best protection from leaf miners is to try to keep the adults from laying eggs that can develop into these larva which may mean Floating Row Covers or careful applications of pesticides, although those can also kill off the predators that could help control them as well. Here is a link that might be useful: about leaf miners

janesylvia, I agonized over this issue also - I feel your pain! lol. I'm a homeowner, kitchen cabinets were oak with a kind of pinkish finish popular in the 90's I've been told? They were looking bad. I replaced the uppers with new cabinets (to extend to ceiling) but lowers, I painted and they look great! Then I took the old uppers and put in the laundry room...painted same white as in kitchen and they also look great. I did try the rollers, various types, but all left exactly what you mentioned, a line. Some very slight bubbling too. Spraying was above my skill set. Instead I used a good brush (Purdy's, my fav!) Gosh, with oak, the grain is gorgeous coming through and *in my opinion* the brush application is a nice compliment to the entire look. I don't notice any brush strokes although I'm sure they're there, just not readily visible with the oak graining. I painted the cabinets white. I heard all kinds of nays on doing that, painting them myself,the color, yada yada yada, but I love the finished look. It is not a smooth finish, like glass or something, it has some character. It might not be a look for everyone but for me and everyone that sees it, it's a winner. I washed the cabinets real good, let dry real good, lightly sanded, did a tack cloth several times over to get any lint, sawdust off and then took the plunge. I used a newer product (newer at the time, which was within this past year) which was an all-in-one paint available at HD. "Behr Premium Plus Stain Blocking Paint and Primer in One." Had it tinted to the white color I selected. I went with semi-gloss finish but I think that's a personal choice, to each their own on the sheen level. I don't find these cabinets to be overly shiny. Honestly, just figured might as well try painting them myself. Luckily it worked well for me..I did of course try one small door panel first to be certain this was a go. Also one last piece of advice: allow them to dry FOREVER before using and definitely wait on adding hardware, like handles or pulls until the paint is dried/cured/whatever the professional term is for that! This was my experience and it turned out well. I hope the same for your project if you decide to tackle it. Best wishes!