(1) - the right decision. Do not try to impose on the user the way you view who likes you or someone else. Let him use the one that suits him, and which it is configured (download, browsing tools browser-and, for that matter).
(2) - bad decision, because the built-in page viewer steals screen space, and if not steal, then this is equivalent to (1) in the case of viewing the media browser-and. Especially bad that all sorts of things, showing the reversal, not the page. It's horribly uncomfortable and you need only one case, which must be strictly avoided when, for example, have a PDF laid out for printing on facing pages, where the content passes from one page to another (as happens with directories) and without having to see the entire spread, it is simply impossible to read.
(3) - even the most disgusting decision, because you will loose the ability to copy text, change the scale to see vector illustration, etc.
General advice: in this case (and indeed, usually) should go from useful functionality, not ornamentation or subjective criteria like "looks cheap", "too easy" (just for whom and why?).
jason.Lueilwitz6 answered on March 12th 20 at 08:14
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