try setting this to false in appsettings.json

"SanitizeTinyMce": true,

Thanks for your answer.

i tried that too

"SanitizeTinyMce": false,

and

"RichTextEditor": {
     "ValidElements": "+a[id|style|rel|data-id|data-udi|rev|charset|hreflang|dir|lang|tabindex|accesskey|type|name|href|target|title|class|onfocus|onblur|onclick|ondblclick|onmousedown|onmouseup|onmouseover|onmousemove|onmouseout|onkeypress|onkeydown|onkeyup],-strong/-b[class|style],-em/-i[class|style],-strike[class|style],-u[class|style],#p[id|style|dir|class|align],-ol[class|reversed|start|style|type],-ul[class|style],-li[class|style],br[class],img[id|dir|lang|longdesc|usemap|style|class|src|onmouseover|onmouseout|border|alt=|title|hspace|vspace|width|height|align|umbracoorgwidth|umbracoorgheight|onresize|onresizestart|onresizeend|rel|data-id],-sub[style|class],-sup[style|class],-blockquote[dir|style|class],-table[border=0|cellspacing|cellpadding|width|height|class|align|summary|style|dir|id|lang|bgcolor|background|bordercolor],-tr[id|lang|dir|class|rowspan|width|height|align|valign|style|bgcolor|background|bordercolor],tbody[id|class],thead[id|class],tfoot[id|class],#td[id|lang|dir|class|colspan|rowspan|width|height|align|valign|style|bgcolor|background|bordercolor|scope],-th[id|lang|dir|class|colspan|rowspan|width|height|align|valign|style|scope],caption[id|lang|dir|class|style],-div[id|dir|class|align|style],-span[class|align|style],-pre[class|align|style],address[class|align|style],-h1[id|dir|class|align|style],-h2[id|dir|class|align|style],-h3[id|dir|class|align|style],-h4[id|dir|class|align|style],-h5[id|dir|class|align|style],-h6[id|style|dir|class|align|style],hr[class|style],small[class|style],dd[id|class|title|style|dir|lang],dl[id|class|title|style|dir|lang],dt[id|class|title|style|dir|lang],object[class|id|width|height|codebase|*],param[name|value|_value|class],embed[type|width|height|src|class|*],map[name|class],area[shape|coords|href|alt|target|class],bdo[class],button[class],iframe[*],figure,figcaption,video[*],audio[*],picture[*],source[*],canvas[*],script[*]"
   }

I'm on 13.4.0 and am able to add script tags by adding script[*] to the list of validelements

Thanks for your answers

i noticed that it works with an RTE on a DoctumentType but what i really need is an RTE on a Element Type that i populate on a Block List

so this is before submit:

and this is after submit

I had the same issue after modifying the appsettings.json. However, it is important to remember to do something like clean the solution and rebuild after making the updates to appsettings. If you just try a build, the project won't rebuild and bind the new RichTextEditor: ValidElements correctly. I could only make this work by forcing a build. I can now add <script> tags with no issue.

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