Preconditions (*)

1. Magento 2.4-develop
2. Both Magento 2.4.0 and 2.4.1
3. PHP version 7.4.11

Steps to reproduce (*)

1. Go to Marketing > Communications > Email Templates
2. Click Add New Template
3. Fill out the form and save. You'll be sent over to the Email Templates grid.
4. Click Preview on the newly created Email Template. You'll notice it will pop-up a preview window and also direct the user away from the Email Templates grid to the template preview.

Expected result (*)

1. Upon clicking Preview, only a preview pop-up window should be displayed. It should not direct the user away from the Email Templates grid. This requires users to click back on the browser to view the Email Templates grid.

Actual result (*)

1. Upon clicking preview, you'll notice it will pop-up a preview window and also direct the user away from the Email Templates grid to the template preview as shown below. This requires users to click Back on the browser in order to return to the Email Templates grid.

Note: Provided screen shot was generated using Chrome. Firefox creates a new tab instead of a new popup, but experiences the same behavior.

2. As a note, two separate requests are made upon clicking Preview. The two requests are listed below.

• /admin/email_template/preview/id/1/key/5557c74ad6bc99b53a5b04afa8d26ec457a180e1cc6fdef15ad7e4a88aa1171e/
• /admin/email_template/popup/key/b6de22c72d421f64469acdb1cf2546fbb891babe071c2b509630ce52fef24bfd/

Please provide Severity assessment for the Issue as Reporter. This information will help during Confirmation and Issue triage processes.

• Severity: S0 - Affects critical data or functionality and leaves users without workaround.
• Severity: S1 - Affects critical data or functionality and forces users to employ a workaround.
• Severity: S2 - Affects non-critical data or functionality and forces users to employ a workaround.
• Severity: S3 - Affects non-critical data or functionality and does not force users to employ a workaround.
• Severity: S4 - Affects aesthetics, professional look and feel, “quality” or “usability”.