[Python] Wagtail default template field in_preview_panel is fine in dev but fails in production

In the default template from Wagtail even mentioned online here, there is a part:

{# Force all links in the live preview panel to be opened in a new tab #}
{% if request.in_preview_panel %}
<base target="_blank">
{% endif %}


I extend this base template in my other templates.

This is fine in dev, but when running the website in production, I face with this error:

Exception while resolving variable 'in_preview_panel' in template 'home/home_page.html'.
Traceback (most recent call last):
File "/home/myusername/.local/lib/python3.12/site-packages/django/template/base.py", line 880, in _resolve_lookup
current = current[bit]
~~~~~~~^^^^^
TypeError: 'WSGIRequest' object is not subscriptable

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/home/myusername/.local/lib/python3.12/site-packages/django/template/base.py", line 890, in _resolve_lookup
current = getattr(current, bit)
^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'WSGIRequest' object has no attribute 'in_preview_panel'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/home/myusername/.local/lib/python3.12/site-packages/django/template/base.py", line 896, in _resolve_lookup
current = current[int(bit)]
^^^^^^^^
ValueError: invalid literal for int() with base 10: 'in_preview_panel'

During handling of the above exception, another exception occurred:

...


I have no clue on what in_preview_panel is and why it behaves different in dev and prod.

If I remove it, this case of error will be resolved. I have still other problems in my code. But, I do not want to remove this blindly or impacting the Wagtail admin. Instead, I want to understand what is happening.

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