When using Shift + Click, internal links are not handled correctly

[rozsazoltan]

Problems

1. ShiftClick on a conversation downloads HTML as a .png file

   When I ShiftClick a conversation, the app starts downloading an HTML document, but the downloaded file uses a .png extension.

   This download is unnecessary. Since this is an internal Messenger navigation link, the app should intercept and suppress the default external/link download behavior when Shift is held.

2. ShiftClick on a photo opens the image in a new window, but the header layout is broken

   When I ShiftClick a photo, it opens in a new window as expected, but the header overflows / sticks out of the layout.

   The current CSS rule that hides the Facebook header does not work correctly on the photo page. The photo view needs a different CSS override than the regular Messenger page.

Expected behavior

• ShiftClick on internal Messenger conversation links should be swallowed/intercepted and should not trigger a file download.
• ShiftClick on photos should open the photo view correctly.
• The Facebook header should be hidden properly on photo pages as well, using page-specific CSS if needed.

Actual behavior

• Conversation links trigger an unnecessary HTML download with a .png file extension.
• Photo links open in a new window, but the page layout is broken because the header is not hidden correctly.

Notes

This likely needs two separate fixes:

• Detect and intercept internal Messenger navigation links when Shift is pressed.
• Apply a different CSS rule for hiding the Facebook header on photo viewer pages.