Title: Warning: undefined array “slug” Last modified: March 29, 2025 --- # Warning: undefined array “slug” * [ilpiac](https://wordpress.org/support/users/ilpiac/) * (@ilpiac) * [1 year, 1 month ago](https://wordpress.org/support/topic/warning-undefined-array-slug/) * Hi, * I’ve just bumped into a problem I never had before. I’m using the LeanCV theme on a website I’m working on locally (mac). I first disabled the webfonts of the theme because they’re all active, and they’re a lot. All worked fine. I then installed Yabe Webfonts to use it with a typeface from Adobe and a custom uploaded webfont too. I activate Yabe webfonts, and that’s fine, but as soon as I set a webfont (Adobe or the custom uploaded one), WordPress shows me a warning. Two, in fact: Warning: Undefined array key “slug” in /Users/xxxxx/Local Sites/xxxxx/ app/public/wp-includes/class-wp-theme-json.php on line 2101Warning: Undefined array key “slug” in /Users/xxxxx/Local Sites/xxxxx/app/public/w-includes/class- wp-theme-json.php on line 2147 * The warnings don’t show if Yabe is installed and active, but without active webfonts. They show as soon as I activate a font. And if I disable Yabe webfonts, warnings disappear. I tried to set php.ini so that it should not show any warnings (as per what a friend of me that’s a dev told me), but it doesn’t work. I’ve tried this because apart from being there, warnings don’t break anything so not showing them should fix my problem. Anyway, no success. * Never had this problem before with Yabe, but since I’m not a coder/developer I don’t know how to solve this in a different way. Thanks! Viewing 4 replies - 1 through 4 (of 4 total) * Plugin Author [Sua](https://wordpress.org/support/users/suabahasa/) * (@suabahasa) * [1 year, 1 month ago](https://wordpress.org/support/topic/warning-undefined-array-slug/#post-18390355) * hi [@ilpiac](https://wordpress.org/support/users/ilpiac/), * I tried to reproduce the issue, but couldn’t get the issue happened as you described. Could you give a detailed step by step to produce it? * Thread Starter [ilpiac](https://wordpress.org/support/users/ilpiac/) * (@ilpiac) * [1 year, 1 month ago](https://wordpress.org/support/topic/warning-undefined-array-slug/#post-18390466) * [@suabahasa](https://wordpress.org/support/users/suabahasa/) * Sure thing. And thanks a lot: 1. Install LeanCV theme and activate it 2. Install Yabe Webfonts and activate it 3. Deactivate all fonts available in LeanCV theme using the FSE style feature ( there are a lot of Webfonts active in that theme, really too many) 4. Activate some Adobe webfonts and upload a custom font too in Yabe * That should get you to the warnings I wrote about. If I disable Yabe plugin the warnings disappear, and they are back as soon as I activate it again. * Sincerely speaking that surprised me a lot since I’ve used Yabe Webfonts in so many personal websites with no problems at all and I was going to buy a perpetual agency license in fact. * I also thought it could be because of something strange in my local development environment, but I’m using LocalWP as usual. * Thread Starter [ilpiac](https://wordpress.org/support/users/ilpiac/) * (@ilpiac) * [1 year, 1 month ago](https://wordpress.org/support/topic/warning-undefined-array-slug/#post-18390477) * [@suabahasa](https://wordpress.org/support/users/suabahasa/) I’ve just tried WordPress Studio too trying to see if the problem could be LocalWP, but the warnings are still there: 1. Downloaded and installed Studio for Mac 2. Installed LeanCv theme and disactivated all the webfonts available and active in that theme (no warnings of sort) 3. downloaded and installed Yabe Webfonts: still no warnings 4. activated some Adobe webfonts using a project ID: warnings appear * Since the warnings are already there, I haven’t uploaded any custom font in this case. * Thread Starter [ilpiac](https://wordpress.org/support/users/ilpiac/) * (@ilpiac) * [1 year, 1 month ago](https://wordpress.org/support/topic/warning-undefined-array-slug/#post-18390510) * After some more tests I can tell you that: 1. the same happens with another theme, Pulitzer, as soon as I activate some fonts with Yabe Webfonts. So I suppose the problem can’t be the theme, also because the file […]app/public/wp-includes/class-wp-theme-json.php is outside the theme’s folder 2. Same problem with variable and not variable fonts * But I can tell you that while I was googling for info I’ve bumped into a problem reported by a Bricks’ user on their forum that, don’t know why, kind of made me think of the problem I have with Yabe. Never tried Bricks and I’m not a developer so the two things can be totally a different thing but this is the link, just in case: [https://forum.bricksbuilder.io/t/solved-adobe-fonts-not-loading-in-specific-instances-due-to-incorrect-assumptions-in-bricks-code/26598](https://forum.bricksbuilder.io/t/solved-adobe-fonts-not-loading-in-specific-instances-due-to-incorrect-assumptions-in-bricks-code/26598) Viewing 4 replies - 1 through 4 (of 4 total) The topic ‘Warning: undefined array “slug”’ is closed to new replies. * ![](https://ps.w.org/yabe-webfont/assets/icon-256x256.png?rev=2926323) * [Yabe Webfont - Use Custom Fonts, Google Fonts or Adobe Fonts](https://wordpress.org/plugins/yabe-webfont/) * [Support Threads](https://wordpress.org/support/plugin/yabe-webfont/) * [Active Topics](https://wordpress.org/support/plugin/yabe-webfont/active/) * [Unresolved Topics](https://wordpress.org/support/plugin/yabe-webfont/unresolved/) * [Reviews](https://wordpress.org/support/plugin/yabe-webfont/reviews/) * 4 replies * 2 participants * Last reply from: [ilpiac](https://wordpress.org/support/users/ilpiac/) * Last activity: [1 year, 1 month ago](https://wordpress.org/support/topic/warning-undefined-array-slug/#post-18390510) * Status: not resolved