Thmubnail and event image collision

Hi there,

we have a problem with images, which started approx. 1 week ago: all of our thumbnails stopped working, only the default icon is visible now.

When we tried to re-upload all the pictures, it produced very blurry thumbnails + it somehow removed the event image (the big picture, which is displayed above text on single event page). This means we can either:

1) have blurry thumbnails (100x44px) + good quality (big) thumbnail displayed on single event page, while event image is removed somehow (it’s border is still visible but the image itself is missing)
2) display good quality event image, while thumbnail is removed

We were not able to resolve this. Can you please help? We have the latest version of the WP, upgraded database and all plugins are up to date.

Unrelated: for reasons beyond us the Google API key field in the plugin settings is filled with following text:

PO-Revision-Date: 2020-06-11 08:59:48+0000MIME-Version: 1.0Content-Type: text/plain; charset=UTF-8Content-Transfer-Encoding: 8bitPlural-Forms: nplurals=3; plural=(n == 1) ? 0 : ((n >= 2 && n <= 4) ? 1 : 2);X-Generator: GlotPress/3.0.0-alphaLanguage: cs_CZProject-Id-Version: WordPress - 5.3.x

Also, this code is set as the Date and time separator for some reason and we were not able to remove it from both fields in any way.

Thanks.

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