When supplying a template parameter to EmailAuthor how can I make the email body editable?

This question concerns the native /_ui/core/email/author/EmailAuthor system.

I can pass values to the form in the URL like so:

p2_lkid = To field
p3_lkid = Related to field
template_id = ID of template to use

If I select a template manually using the Select Template button on the form then the body of the email (and the template) will be editable inline.
However if I load a template automatically by passing its ID as a parameter to EmailAuthor then whilst the template will load into the body it will become read only.

How can I make the template load automatically into the body whilst retaining the feature to modify edit inline?

Answers:

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Method 1

be sure that the template you are using is not a “Custom” one. You can only edit “Text” and “HTML” templates from that window.

Edit:
try to modify the HTML version of the template from “My Templates” and click on the padlock to unlock the template. If it is already unlock, do it anyways to lock and unlock it.

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