Office Macros won't load when wrapped in a <strong></strong> tag

Issue Summary

Office Macros won't load their content when wrapped in a <strong></strong> tag .
The issue is happening in version 7.13.0 and it's not reproducible in version 7.6.x

Steps to Reproduce

1. Create a new Page in Confluence.
2. Add an Office file (excel, word, or ppt).
3. Add an Office macro to show the file.
4. Select the macro.
5. Select the B in the editor bar to apply the bold effect.
6. Save the page.

Expected Results

The macro should load normally regardless of the strong tag.

Actual Results

Because of the strong tag created by the bold option the macro will not display its content.

I have attached an exported space where we can reproduce the issue.
Also, the storage format of a page with the issue is the following:

<p><strong><ac:structured-macro ac:name="viewxls" ac:schema-version="1" ac:macro-id="c3315c45-a800-4aeb-8275-c4121826cb29"><ac:parameter ac:name="name"><ri:attachment ri:filename="Financial Sample.xlsx" /></ac:parameter></ac:structured-macro></strong></p>
<p><br /></p>

Workaround

The user can remove the tag by editing the affected page, selecting the macro, and selecting the "bold" option in the edit bar.