Viewport not resizing #269

Activity

1. route commented on Jun 29, 2024

   

   route

   on Jun 29, 2024

   Member

   More actions

   I think that's Chrome bug, what version are you using now? What version you used previously and when was the last update?
2. adrianthedev commented on Jun 29, 2024

   

   adrianthedev

   on Jun 29, 2024

   Author

   More actions

   It's Chrome Version 126.0.6478.127 (Official Build) (arm64)
   And cuprite (0.15.1)

   How can I update it?
3. adrianthedev commented on Jun 29, 2024

   

   adrianthedev

   on Jun 29, 2024

   Author

   More actions

   Not sure what I had before. I switched from selenium
4. Nakilon commented on Jun 30, 2024

   

   Nakilon

   on Jun 30, 2024

   More actions

   Does the issue disappear if you remove this line? https://github.com/rubycdp/ferrum/blob/99cfa84c56e55bb373da48935d08d5a13df1ad27/lib/ferrum/page.rb#L169
5. adrianthedev commented on Jun 30, 2024

   

   adrianthedev

   on Jun 30, 2024

   Author

   More actions

   Yes. The issue is fixed by removing that line.
   The page starts working properly now when resizing the browser.

   Thanks!
6. Nakilon commented on Jun 30, 2024

   

   Nakilon

   on Jun 30, 2024

   More actions

   I thought it was fixed: rubycdp/ferrum#203
7. route commented on Oct 15, 2026

   

   route

   on Oct 15, 2026

   Member

   More actions

   This is expected behavior. On every new page, Cuprite sets the window size to window_size (1024×768 by default) and also fixes the page's viewport at that size with Emulation.setDeviceMetricsOverride. That way innerWidth/innerHeight are exactly window_size and tests see the same page size on every machine. This used to happen in Ferrum too (rubycdp/ferrum#203). Ferrum no longer does it, but Cuprite still does, because tests rely on it.

   In headless runs nobody resizes the window, so this has no visible effect. In a visible window (headless: false) it shows up in two ways:

   • Chrome's toolbar takes up part of the window, but the page stays 768px tall, so its bottom is cut off.
   • Resizing the window by hand changes only the window. The page stays 1024×768 and doesn't reflow, which is what your video shows.

   Since #339 (in the next release), you can pass window_size: nil to leave the size to Chrome. Then the page follows the window like in a regular browser:

   Capybara::Cuprite::Driver.new(app, headless: false, window_size: nil)

   Checked in a visible window, resizing it to 1400×900 by hand:

   	Page before	Page after resizing the window
   default window_size	1024×768	1024×768 (stays fixed)
   window_size: nil	1200×818	1400×813 (follows the window)

   Add browser_options: { "start-maximized" => nil } to start maximized. resize_window_to still sets an exact size when a test needs one.
8. route

   closed this as completedon Oct 15, 2026