tcp[13] & 4 == 4 doesn't seem to work on v. 3.4.9

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Hello everyone,

tcp[13] & 4 == 4 doesn't seem to work for me on v. 3.4.9 More specifically the "==4" part doesn't seem to be accepted by the display filter box. (everything's green and nice if you only type "tcp[13] & 4")

I'm quite new in Wireshark... Do i miss something on my syntax? Is there something i have to configure on my Wireshark first?