Once again, I would like to say a word in defense of a passive voice.
What's wrong with it? It exists in the language for a purpose and can be appropriate when used for this purpose.
In this particular case, it might be. Say, if you main concern is that you, or rather the hijack you committed, could be frowned upon - in general, no matter who does the frowning - say, you mean the majority of the readers, not every single one, and not any particular one, then your hijack is the main subject of this sentence, and you don't have to distract attention from that fact. Then, yes, I would say,
"I hope this little semi-related hijack is not too frowned upon."
If, on the other hand, your main concern that no one at all, or not a particular person, or not someone holding some powers, etc. might frown upon your hijack, than, by any means, get rid of the passive voice and accentuate this fact:
"I hope no one frowns upon this little semi-related hijack.",
or
"I hope Such-and-Such doesn't frown upon this little semi-related hijack."
But we have already discussed it in some earlier threads, more than once.