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This process tool plugin sends an email message to the targeted recipient(s), with the ability to use a common body template via hash variable.
You can use $(body) in the Message Body Template to display the content within the Message field.
With that, you can use Environment Hash Variable to create a template with $(body) to display the content within the Message.
You can easily modify the template and affect all that uses said template without ever looking for each email tool plugin and modifying each of them.
JOGET OSS
The plugin is also available open-source at jogetoss/email-tool-with-template.