Example URL:
https://mysteriouscode.io/

Steps to reproduce the problem:
1. Open https://mysteriouscode.io/ in Chrome on iPhone or iPad
2. Icon (/assets/app/uploads/2016/09/logo-square.png) will not be loaded. 
3. Server logs indicate that the request is missing an Accept header (blocked by mod_security)

If the url https://mysteriouscode.io/assets/app/uploads/2016/09/logo-square.png is opened directly in the browser, image is loaded correctly (Accept header is sent). Adding "type="image/png" to <link rel=""> properties on the website made no change.

What is the expected behavior?
Accept header should be sent.  At least "Accept: */*" should be present.

What went wrong?
Example request sent by iPad:
GET /assets/app/uploads/2016/09/logo-square.png HTTP/1.1
Host: mysteriouscode.io
Connection: keep-alive
User-Agent: Mozilla/5.0 (iPad; CPU OS 10_3 like Mac OS X) AppleWebKit/602.1.50 (KHTML, like Gecko) CriOS/57.0.2987.137 Mobile/14E277 Safari/602.1
Accept-Encoding: gzip, deflate, sdch
Accept-Language: en-US,en;q=0.8,pl;q=0.6

Example request sent by iPhone:
GET /assets/app/uploads/2016/09/logo-square.png HTTP/1.1
Host: mysteriouscode.io
Connection: keep-alive
DNT: 1
User-Agent: Mozilla/5.0 (iPhone; CPU iPhone OS 10_3_1 like Mac OS X) AppleWebKit/602.1.50 (KHTML, like Gecko) CriOS/57.0.2987.137 Mobile/14E304 Safari/602.1
Accept-Encoding: gzip, deflate, sdch
Accept-Language: en-GB,en;q=0.8,en-US;q=0.6,pl;q=0.4

Problem does NOT occur in desktop version of Chrome or Safari on iOS, which suggests this is an issue with iOS version of Chrome.

Does it occur on multiple sites: N/A

Is it a problem with a plugin? No 

Did this work before? N/A 

Does this work in other browsers? Yes

Chrome version: 57.0.2987.137  Channel: stable
OS Version: iOS 10.3
Flash Version: