[__NSCFConstantString size]: unrecognized selector sent to instance

[kfateem]

Before images are downloaded, quickly scroll up and down in the the table view. The app will crash with:

[__NSCFConstantString size]: unrecognized selector sent to instance

I believe this is the offending line - TKImageIpsum.m line 107: [cache setObject:placeholder forKey:key ?: placeholder];

The above caches a string instead of a UIImage.

The completion block expects an image and crashes.