iOS apps just show as a blank magenta screen

[JonnyPtn]

Subject of the issue

iOS apps don't render anything, just showing as a blank magenta screen.

Environment

• macOS 10.13, Xcode 9, iOS 11.3
• SFML 2.5.0

Steps to reproduce

Build SFML with the example for iOS and run it

Expected behavior

Should render correctly

Actual behavior

Blank magenta screen

Details

I've tracked it down to commit 0adde24, and more specifically this line which when commented out solves the problem, but my openGL knowledge is too sparse to work out exactly what is causing it.

edit: after some googling and trial-and-error I've found out if I bind the frame buffer in EAGLContext::Display() (add glBindFramebufferOES(GL_FRAMEBUFFER_OES, m_framebuffer); at the top of the function) then it works... I can't say whether this is a good solution or not, so I'm hoping someone else can!