Bug present at least up to version 11.0.0
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a // InputForm
b // InputForm
Gives me
in "11.0.0 for Microsoft Windows (64-bit) (July 28, 2016)" on my desktop and laptop computers. You can see that only the last output using InputForm is displayed. The web-app ( https://mathematica.wolframcloud.com/app ) does what I expect:
This only happens with InputForm, other *Forms display all outputs.
I must have some bad settings, but I cannot figure out what could be the cause. The Suggestions Bar is off and init.m is empty. Any ideas?

