Can I stop the "new css rule" dialog box popping up on text edits?

Hi everyone

I am making an email template for one of our clients. I use <span> to format text.

I put placeholder text, already styled, into the html. The goal being that the client can easily highlight and replace the text from within the design view, not the code.

Anytime one highlights the entire text and either pastes in content or types, up pops a "create new inline style" dialog box that must be canceled 3 times before you can edit the text.

Placing the cursor in the text and typing, or highlighting a portion of the text does not bring up the dialog box (it's only when the entire text is highlighted).

How can I get this to stop?

Here is a sample of the code if it helps.

<span style="font-size: 18px; line-height: 24px; color: #333333; font-family: Arial, Helvetica, sans-serif; font-weight: normal;">Newsletter Statement goes here.</span>

Dreamweaver 19.0 on Mac OS 10.12.6

Thanks

Matt