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Hello Ton, I'm also from Spain and I also have the same problem, it's like the LT and UTC work separetly. I'm using Google Chrome as my browser.
Yup, same feeling here. I would love to support this app, it's absolutely fantastic! If you can't put a Paypal in this page maybe put up a Patreon or something similar? even the pizza idea I saw in other post is better than nothing...