--- title: Minified MUI error #9 slug: minified-mui-error-9 createdAt: 2025-12-11T01:32:50.730Z --- # Issue You get this error when browsing in the Activate web. Error: Minified MUI error #9; visit MuiProduction errorfor the full message.at l (https\://localhost/static/js/main.3eb961cc.js:205:266279)at h (https\://localhost/static/js/main.3eb961cc.js:205:267651)at https\://localhost/static/js/main.3eb961cc.js:205:16715 at Array.map (\)at https\://localhost/static/js/main.3eb961cc.js:205:16515at b (https\://localhost/static/js/main.3eb961cc.js:205:271452)at https\://localhost/static/js/main.3eb961cc.js:205:269320at h (https\://localhost/static/js/main.3eb961cc.js:2:671091)at v (https\://localhost/static/js/main.3eb961cc.js:2:671391)at https\://localhost/static/js/main.3eb961cc.js:205:263293 # Possible Fix Review Resources > Configuration > Web > Theme > Theme.json for any possible constants that may not be handled by MUI, for example white below. ![](https://api.archbee.com/api/optimize/Lfto9rn2ELed8aLNOgwlJ/kDYYNS5Qf-X4Uq1SEg5HH_image.png) Changing this to #fff and restarting the web services may address the issue. After the fix: ![](https://api.archbee.com/api/optimize/Lfto9rn2ELed8aLNOgwlJ/6D0WN8PbV28DXoKZppjGI_image.png)