Wordpress LScache Plugin: UCSS generator error: Cannot read property each of null
Last Updated on: Wed, 15 Apr 2026 00:00:02 Hello, I see this in plugin debug log and also on QC. QC Error: = UCSS generator error: Cannot read property each of null DEBUG LOG: = Please see below. 09/15/21 14:21:41.234 [2.58.28.32:40604 1 56d] response ok --- array ( ucss => / null /, msg => UCSS generator error: Cannot read property each of null, ) 09/15/21 14:21:41.235 [2.58.28.32:40604 1 56d] [CSS] con: / null / 09/15/21 14:21:41.235 [2.58.28.32:40604 1 56d] [CSS] empty ucss [content] / null / 09/15/21 14:21:41.236 [2.58.28.32:40604 1 56d] [CSS] Save URL to file [file] /home/mydomain.co.uk/public_html/wp-content/litespeed/ucss/e5fc61c7ee01798be278bbea7358bce8.css [vary] 09/15/21 14:21:41.239 [2.58.28.32:40604 1 56d] [Purge] added _UCSS.727c6b3f8bc93a152207628d3763c512 => LiteSpeed Purge->_add(ARRAY)@408 => LiteSpeed Purge::add(UCSS.727c6b3f8bc93a152207628d3763c512)@386 => LiteSpeed CSS->_save_con(ucss,/ null /, https://www.mydomain.co.uk/ganga-jali-3-drawer-drum-chest)@512 => LiteSpeed CSS->_send_req(https://www.mydomain.co.uk/ganga-jali-3-drawer-drum-chest, https://www.furnituresuppliesu)@462 => LiteSpeed CSS->_cron_handler(ucss)@350 => LiteSpeed CSS::cron_ucss()@305 => WP_Hook->apply_filters(,ARRAY)@303 => WP_Hook->do_action(ARRAY)@327 => /home/mydomain.co.uk/public_html/wp-cron.php@518 09/15/21 14:21:41.239 [2.58.28.32:40604 1 56d] X-LiteSpeed-Purge: Any tips on how to resolve this please, I hope to resolve it soon because my PAYG quota is getting eaten up pretty fast. Kind regards Probably not related but also this. 9/15/21 15:14:10.498 [149.28.11.90:39542 1 787] [CDN] -rewrite failed: path not match: wp-content 09/15/21 15:14:10.498 [149.28.11.90:39542 1 787] [CDN] matched file_type .gif : /wp-content/themes/porto/css/images/fancybox_loading.gif 09/15/21 15:14:10.498 [149.28.11.90:39542 1 787] [CDN] rewrite /wp-content/themes/porto/css/images/fancybox_loading.gif 09/15/21 15:14:10.499 [149.28.11.90:39542 1 787] [CDN] -rewrite failed: path not match: wp-content Hello @furnituresuppliesuk This means in your css content you have pseudo-class :not and you are using it without parentheses, which is a css error. Please correct this and it should be ok. We found that out but havent got chance to implement it into the code and send to user yet. But will do it soon. Best regards, Abe Hi Abe, Thank you for the info, I have tried running a search on my server for files that contain such contents, too many results returned so I will probably just wait for next update. Many thanks again. Lee
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