I already replied to your first post. This is WordPress doing the image compression. See here how to change the quality:
https://www.wpbeginner.com/wp-tutorials/how-to-increase-or-decrease-wordpress-jpeg-image-compression/
Thread Starter
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(@hongson4787)
Thank for responde Ron, but it seem like do not work. I try to test by change to another theme, the thumbnail image look very clear and beauty.
Thread Starter
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(@hongson4787)
https://prnt.sc/mxui08
This frontier theme
https://prnt.sc/mxukzo => this understrap theme
https://prnt.sc/mxulti => this wordplus theme from themejunkie
I like your theme and everything is so good, i just want to make the thumbnail look more clear.
Your problem does seem to be image compression. The theme does not compress images WordPress does. The link I posted above explains how to undo that. Or you could try this plugin https://wordpress.org/plugins/disable-jpeg-compression/
Remember to regenerate the thumbnails after so the changes are reflected. Make sure to refresh any image caching you may have like Cloudflare.
Thread Starter
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(@hongson4787)
Follow your way but it not resolve my problem.
