Originally Posted by RoninTech
Weird. Wife and I both have Kobo Glos that we used on a beach in Thailand for a month earlier this year. Extremely hot and humid and had no issues whatsoever.
How often do you have the page refresh set to? If you refresh every few pages, you won't see the lines on the screen.
If you try to extend battery life (like many of use) and push the refresh beyond what Kobo allows (1-6), that's when the dark lines will start forming.