Multiple RenderTextures with same source only draws first instance, rest throws WebGL error

[AleBles]

This Issue is about (✏️ delete as applicable)

• A bug in the API:

  • Phaser version(s): >=2.7

  • Live example: http://cdn.fbrq.io/phaser-nineslice/example/issue.html

  • What should happen: Second instance of RenderTexture with same origin should be drawn

  • What happens instead: It isn't drawn

This affects users of my library (phaser-nineslice). I could ofcourse also rewrite it to not use RenderTextures, but after seeing http://www.html5gamedevs.com/topic/27041-gldrawelements-source-and-destination-textures-of-the-draw-are-the-same/#comment-165755 I tought I'll just report it.