CSS classes can’t be applied to standard WYSIWYG content


Getting this error when I submit a template in the marketplace. I check all the custom modules in this template and check the Richtext but there's no CSS class content found in this WYSIWYG/RichText module.


Please help me what is the solution for this error:



CSS classes error promptCSS classes error prompt

4 Replies 4
HubSpot Alumni

Hi @ryanl_rise,


Did you get this one figured out? If not I'm happy to give your template a look and figure out why that error is getting thrown. Feel free to link me here or through a direct message.


Leland Scanlan

HubSpot Developer Support

Hey there, 


Did you guys found the solution for this ? I am trying to create bunch of email templates with 2020 trends and while trying to submit one email template, encounter the same errors. 


  • CSS classes can’t be applied to standard WYSIWYG content.
  • CSS classes can’t be applied to standard WYSIWYG content in custom modules.

I am not sure what is wrong. 


Can you help me if you have sorted this out already ?


Thanks in advance. 


Contributor | Diamond Partner

Same here. Was anyone able to figure this out?


I actually found what was causing the issue. 


In my case, even I was not using the Rich Text module anywhere in the email template, but it was been added in the fields, it was throwing me an error. 


So make sure you did not have any Rich Text added into your custom module if you are not using it anywhere. 


Check the attached image to see where I mean to say. Under the Fields  if you have unused Rich Text it will throw an error. 


To find out how you can verify is, in your template, try to add each one by one module. Try to submit it, if it goes to the next step, that mean the module is good. Then try to add another module and re-submit. Keep going until you find the culprit module. 

I know it's tidious process but I get solution this way at the end. I hope this helps you guys too.
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