Really? That really sucks. It would make uploading videos a little bit easier. Thanks for letting me know though

There's no way to automagically make them stay for now, to my knowledge. 

Seems like the only way is to save them to a document or copy them from a previous video. But this is a really good idea. 

In case the title isn't clear, I usually use the same hashtags in my videos and was wondering if the hashtags can be saved in the description by default?

I can input them fine in the default window, but they don't save. If not, consider this my suggestion for a maybe potential update ;)

Saving Hashtags to Default Description