Wordpress LScache Plugin: Webp not delivering (With Log)
Last Updated on: Wed, 15 Apr 2026 00:00:02 Hi, I found out that WebP images are not delivering to my website. I have enabled all setting related with WebP and I have checked my htaccess file, which containing code related with WebP already. What should I do? I tried to delete all Optimized image and run it again, but I got this error: Failed to post via WordPress: hash does not match: ClientCB[wrong passive callback] Server[lR2jotjwcU0drJ1p] WebP related code in my htaccess: ### marker WEBP start ### RewriteCond % HTTP_ACCEPT image/webp [or] RewriteCond % HTTP_USER_AGENT Page Speed RewriteRule . - [E=Cache-Control:vary=% ENV:LSCACHE_VARY_VALUE +webp] ### marker WEBP end ### Thank you for reading and your help. This topic was modified 2 years, 11 months ago by Marius L. J.. Reason: Removed logfile The page I need help with: https://www.howtostudycantonese.com/ I tried to delete all Optimized image and run it again, but I got this error Did you install any firewall recently? If yes, please follow https://www.litespeedtech.com/support/wiki/doku.php/litespeed_wiki:cache:lscwp:image-optimization#server_list to add IP whitelist, after that, try to Clean Up Unfinished Data > Reset IAPI Key > Send Optimization Data Then, please check on media page to are the images get the webp version. Hi @kghugo2000, just checked you site the images already replaced by webp. Are you using Firefox 66 to 71? Firefox removed?image/webp?from the navigation API, thus webp replacement wont happen in versions of Firefox 66 to 71 ? Firefox is bringing back this functionality in version 72, and then webp replacements will start working again. You can try to use Google Chrome for checking first. Hi, Thank you so much for your help. No I was not using Firefox but I forgot I have disabled optimization for admins. The problem is solved. Thank you! Yours sincerely, Hugo Sum
LiteCache Rush: Speed comes from using less, not from doing it faster
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