Finally!
Found some issues regarding Content-Security-Policy (CSP) and the “gap://ready” error I’ve found previously:
- password popup never shows on iOS10 #501;
- White screen on iOS 10 (new) #7052;
- White screen on iOS 10 #6928;
Just replaced my CSP meta tag from this …
<meta http-equiv="Content-Security-Policy" content="default-src *; script-src 'self' 'unsafe-inline' 'unsafe-eval' *; style-src 'self' 'unsafe-inline' *">
… to this (notice the “gap:” in the “default-src” attribute) …
<meta http-equiv="Content-Security-Policy" content="default-src gap: *; script-src 'self' 'unsafe-inline' 'unsafe-eval' *; style-src 'self' 'unsafe-inline' *">
… and everything worked fine.
My GitHub repository is already updated with the correct CSP.