Thanks for looking into it. Looks like it’s only able to be adjusted/sticky for Desktop.
Topic summary
Main Issue:
After updating to the latest Dawn theme, the hamburger menu fails to open on mobile devices.
Root Cause Identified:
The problem stems from broken HTML structure rather than CSS. An improperly added SEO app creates duplicate <html> opening tags, causing the browser to ignore the second tag. This results in the <html> element having class “no-js” instead of “js”, which prevents the menu from functioning. Shopify removed “no-js” handling in recent Dawn versions, requiring the “js” class for proper operation.
Solution:
Delete the problematic SEO app code causing the duplicate HTML tags. Once removed, the menu works correctly.
Related Issues:
- One user reported the hamburger menu appearing at the bottom of mobile screens instead of the header (theme feature, not a bug)
- Another user found their hamburger menu broken due to a popup feature; disabling the popup temporarily fixed it, but they need both features working simultaneously (unresolved)
Status: Primary issue resolved; one case remains open regarding popup/menu conflict.
