Wordpress LScache Plugin: Generated Critical CSS contains only null /
Last Updated on: Wed, 15 Apr 2026 00:00:02 Hello, In my site, I have load css async and generate critical css enabled. Generate critical css in background is disabled. The critical css generated for front page and any other page (see here) always just contains / null / comment. Hence, FOUC is always present. Ive tried to enable background generation, but that gives the same result. Report number: CWJBUPID Report date: 04/22/2019 21:48:00 Thanks for any assistance. Ivan. The page I need help with: https://sample.rideelectricbikes.co.nz/ Due to rapid growth of active installations, we got some heavy loads for CCSS online services. We just improved the server capability to better handle the requests. Now it should be fine. Please try more. If you still meet the null CCSS issue, please check your debug log and see what it says when fetching CCSS. Hello! Its still unable to generate using ccss. 04/23/19 10:11:17.974 [:55040 1 xjA] [CSS] cron job [type] front [url] https://sample.rideelectricbikes.co.nz [U$ ] Mozilla/5.0 (Windows NT 10.0 Win64 x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.3683.103 Safari/5$ 7.36 04/23/19 10:11:17.977 [:55040 1 xjA] [CSS] Generating: --- array ( home_url => https://sample.rideelectricbikes.co.nz, url => https://sample.rideelectricbikes.co.nz, ccss_type => front, user_agent => Mozilla/5.0 (Windows NT 10.0 Win64 x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.$ 683.103 Safari/537.36, is_mobile => 0, ) 04/23/19 10:11:17.981 [:55040 1 xjA] [IAPI] posting to : https://as.wp.api.litespeedtech.com/ccss 04/23/19 10:11:18.403 [:55040 1 xjA] [IAPI] failed to decode post json: 503 Service Unavailable 503 Service Unavailable The server is temporarily busy, try again later! 04/23/19 10:11:18.411 [:55040 1 xjA] [CSS] empty ccss Expand Can you try it now? Thanks. Hi,its back to the original issue now: 04/23/19 19:22:32.565 [:33052 1 apT] [CSS] saved ccss /usr/share/nginx/html/sample.rideelectricbikes.co.nz/wp-content/cache/ccss/product.css 04/23/19 19:22:32.565 [:33052 1 apT] [CSS] ccss con: / null / Just fixed a deployment issue. Do you mind to try it now? Hello, its still the same. I checked the generated file and it only contains / null / 04/24/19 11:56:51.727 [:43114 1 H8W] [CSS] saved ccss /usr/share/nginx/html/sample.rideelectricbikes.co.nz/wp-content/cache/ccss/front.css 04/24/19 11:56:51.727 [:43114 1 H8W] [CSS] ccss con: / null / Are you able to see any clues on your server as to why it might be generating this way? Hi @ivankyli, we found your site contain css error: CssSyntaxError: /min/c2bf3.css:8:545292: Unknown word could you please take a look at the CSS script, you can turn off CSS Minify for easier checking. Hello, Ive fixed the CSS issue but still getting empty response from ccss generation: 04/25/19 10:24:51.122 [:56224 1 Avb] [CSS] cron job [type] front [url] https://sample.rideelectricbikes.co.nz [UA ] Mozilla/5.0 (Windows NT 10.0 Win64 x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.3683.103 Safari/53 7.36 04/25/19 10:24:51.126 [:56224 1 Avb] [CSS] Generating: --- array ( home_url => https://sample.rideelectricbikes.co.nz, url => https://sample.rideelectricbikes.co.nz, ccss_type => front, user_agent => Mozilla/5.0 (Windows NT 10.0 Win64 x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.3 683.103 Safari/537.36, is_mobile => 0, ) 04/25/19 10:24:51.130 [:56224 1 Avb] [IAPI] posting to : https://as.wp.api.litespeedtech.com/ccss 04/25/19 10:25:06.139 [:56224 1 Avb] [IAPI] failed to post: cURL error 28: Operation timed out after 15001 millis econds with 0 bytes received 04/25/19 10:25:06.139 [:56224 1 Avb] [CSS] empty ccss From my server I can wget https://as.wp.api.litespeedtech.com/ccss Any other clues as to whats happening? Seems that your site is too large for generating CCSS within 15 sec, could you try to edit wp-content/plugins/litespeed-cache/admin/admin-api.class.php row 383: From $response = wp_remote_get( $url, array( timeout => 15 ) ) To $response = wp_remote_get( $url, array( timeout => 30 ) ) for increasing the timeout? Hello, Thanks for the tip. Although Im really surprised that would be the issue since my front page is only 546KB and fully loads within 2.0s according to gtmetrix.. What user agent does your server query with? Or any way to identify the request from server logs? Just want to make sure Im receiving the request on the server. Thanks, Ivan. Hi, just updating the issue. Increasing the timeout to 60s solves the issue. Is it possible to increase this timeout permanently in future releases of this plugin? Thanks for your help, Ivan.
LiteCache Rush: Speed comes from using less, not from doing it faster
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