Yun web panel asks to login at every click

Hi, after a period of stable functioning and apparently without touching anything on the OpenWrt side of the Yun, the web panel started asking to login at every click. It's pretty strange and annoying too, it started with 1.5.2 firmware version, then I updated to 1.5.3 but nothing changed. The only thing that comes me to mind is that I expanded the filesystem to the SD card, it seems that the problem started few periods after that (not immediately after though...).

Maybe I figured out the “problem”: if I upload a sketch like TemperatureWebPanel that uses the built-in webserver and I open the page in meantime of yun management I experience what I described (management keeps asking password)… Weird but somehow…