Notice: Undefined index: cat in canonical.php on line 128

[dd32]

By the look of it, Canonical seems to be accessing GET items without first checking if they exist, See attached patch

[hakre]

I just had only a quick look, maybe isset() needs to be used in case the get variable/index is not set?

[dd32]

Thats what empty() is being used for.

isset() And empty() do not issue the undefined warnings, Isset is good when you just want the index to be set, empty() is better when you want it to be set, and have a non-empty value.

[ryan]

(In [12202]) Fix undefined index notice in canonical. Props dd32. fixes #11057