javascript - How can Internet Explorer render same source in different ways? -

javascript - How can Internet Explorer render same source in different ways? -

this question might broad have no specific code show problem have. it's impossible anyway.

i using net explorer 11 open web page generated on system. take page source, re-create content text-file, , replace references external javascript file, stylesheet file etc. local directory. create sure local directory contain exact same javascript files, stylesheets etc.

when open copied html source in 2 tabs of same net explorer browser, contents shown differently! pretty sure no other files included somewhere in javascript, stylesheet, ... files. how possible, same source can rendered in different ways? there can check or investigate?

additional information:

on firefox browser original , copied page shown same way, far eyes can tell. i have cleared browser

if people think question not belong here, please suggest improve place inquire question.

what gets lost when save file , open file http headers. specifically, http content-type header instructs browser kind of document treat info as. may server instructs browser treat document xhtml (hypothetically); when open document it's treated pure html soup. may trigger difference in when quirks mode used, can lead subtle or not-so-subtle differences. there may other headers triggering same or other things, problem , difference pretty certainly lack of http headers.

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