For [USER=144593]@Reinhard[/USER] as Reply ...
My main concern was/is minimizing unwanted MEDIA (images ; videos) related data flow via the SPOILER feature. Your suggestion, as I understand it, seems more complex. And also, some websites actually do NOT want 'normal level' USERS to be able to exercise an almost 'censorship' level of control on a given THREAD.
The data flow level of 'clickable' URLs and TEXT content, seems not that much. So, NOT clear to me that those need to be 'forced' into a SPOILER mode somehow. But MEDIA data flow, can be quite a bit. I have seen THREADS where some USER posts a LOT of ani-GIFs and high pixel density HQ Images ; and also a LOT of embedded YOUTUBE videos. It can take (time duration) AWHILE for that MEDIA data flow to feed through to anyone that opens the THREAD. Hence my original suggestion.
I would describe my original suggestion as a more 'minimalist' one ; ONLY to 'force' SPOILER feature on the MEDIA content. Whereas, your suggestion seems a more COMPLEX one. I would settle for my suggestion, as perhaps one that is less complex, and thus more achievable as a goal. Also, my original suggestion grants the THREAD ORIGINATOR a minimal ability to control (censor?) content posted by other USERS.
NOT meaning to say that your more COMPLEX suggestion is a 'bad one' somehow. Only observing that from a DATA FLOW minimization viewpoint, that my suggestion of 'forced' SPOILER feature on MEDIA (only) seems the more desirable 'minimalist' choice here.
Thanks for your reply. It is clear that you see merit in my suggestion. So, I feel complimented by that. 
