Bug: ":stories" crashes with "TypeError: 'NoneType' object is not subscriptable" after successful login

Environment

• Instaloader version: Latest release (up to date at the time of reporting)
• Python: 3.12
• Operating System: Windows 11
• Browser used for cookie import: Opera Stable (Also tried with firefox, librewolf)
• Opera installation: Standard installation (not Opera GX, not portable)

Command used

instaloader --load-cookies Opera --cookiefile "C:\Users\abird\AppData\Roaming\Opera Software\Opera Stable\Default\Network\Cookies" :stories

What happens

Instaloader successfully imports cookies and logs into Instagram:

Cookies loaded successfully from opera
<username> has been successfully logged in.
Next time use --login=<username> to reuse the same session.
Retrieving all visible stories...

Immediately after that, it crashes with:

Traceback (most recent call last):
  ...
  File "...instaloader.py", line 855, in download_stories
    for i, user_story in enumerate(self.get_stories(userids), start=1):
  File "...instaloader.py", line 811, in get_stories
    userids = list(edge["node"]["id"] for edge in data["feed_reels_tray"]["edge_reels_tray_to_reel"]["edges"])
TypeError: 'NoneType' object is not subscriptable

The traceback indicates that "data["feed_reels_tray"]" is "None".

Expected behavior

Instaloader should either:

1. Download the visible stories from followed accounts, or
2. Gracefully handle the case where "feed_reels_tray" is "null" instead of raising an uncaught "TypeError".

Additional information

• Cookie import succeeds.
• Login succeeds.
• I can access Instagram normally in Opera.
• I can see stories normally on instagram.com in the same Opera session.
• The Opera cookie database exists at:

C:\Users<username>\AppData\Roaming\Opera Software\Opera Stable\Default\Network\Cookies

• Instaloader successfully creates and saves its own session.
• The problem occurs every time I use ":stories".

Additional testing

I also tested downloading a public profile (e.g. "nasa"), and Instaloader was able to authenticate and download posts, although I occasionally saw transient GraphQL "403 Forbidden" retry messages before continuing.

This suggests that authentication and the saved session are working correctly, and the issue appears to be specific to the ":stories" retrieval path.