Ah, just saw it. Do you want to have round corners added to the banner? Could you use this one instead? I made it a PNG so the corners are transparent. The one you adjusted seems to be of low quality which makes it uneasy to read the text, in particular, the dates.

Cheers!

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<a href="https://steemfest.com"><img src="https://files.steempeak.com/file/steempeak/rubencress/TdasrV2W-steemfest-round-corner.png" alt="Meet me at SteemFest 2018 in Kraków" /></a>
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