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1. Create a page with the following content:
====Navigable Table Of Contents 2====
{{test | foobar=kajhsadjkhdsjasdhjh123123 }}

2. Save the page and then edit it. You should see the wrapped "test" template widget.

3. Place the cursor at the begining of the line before the "====Navigable Table Of Contents 2====" and paste some multiline HTML content

4. Repeat step 3 a few times.

5. On the 2nd or 3rd paste will see that the "test" template gets automatically unwrapped into a line that looks like this
test{{test | foobar=kajhsadjkhdsjasdhjh123123 }}