firefox should render unrecognized text/* as text/plain

The problem with this is that the user then has no good way to associate the
content to an application.

It would make more sense, imo, to implement "view in browser as text" as a way
to handle an arbitrary MIME type and then let users set it as needed.

That would be better than the current situation, but suboptimal in that it would
present the user with a dialog in a number of cases where a dialog should be
avoided (that is, cases where it is overwhelmingly likely that the user would
prefer to see the content in the browser by default).

Isn't browser handling of a type already overridden by the presence of a helper
app entry for that type?

All the common text/* types that we don't already render as text/plain
are not something the user wants to see by default (text/rtf is the only one
I can think of).

And no, a helper app does not currently override internal handling.
Furthermore, the architecture to do it is not in place and putting
it in place would also allow the "view in browser" option.

Note that once a user selects to open a type in the browser, the decision
would get remembered, so the only difference is that the user gets explicit
UI once to decide on a course of action.

*** Bug 216935 has been marked as a duplicate of this bug. ***

*** Bug 215706 has been marked as a duplicate of this bug. ***

*** Bug 108313 has been marked as a duplicate of this bug. ***

Note that if we _really_ decided to do this it would be doable with a stream
converter (and a little magic in URILoader to look for stream converters by
major/*, which I think we may want anyway).

of course stream converters have the issue that they cause a "wrong" type to be
reported on the channel, so document.contentType and page info will have a wrong
type.

maybe nsIChannel needs an "readonly attribute ACString originalContentType"
attribute? (well, a new nsIChannel2 of course)

Two extremely frustrating examples of this bug for me are text/x-chdr and
text/x-csrc. I have a directory tree full of source code that was intended to
be web browsable; however, whenever I try to open links to individual source
files, an dialog box pops up that wants to open a freaking terminal window so it
can page the files through less!! The dialog box (which ideally wouldn't pop up
by default) should at least have an option saying "please render this internally".

Brandon, that's covered by a different bug.

(In reply to comment #1)
> It would make more sense, imo, to implement "view in browser as text" as a way
> to handle an arbitrary MIME type and then let users set it as needed.

I'd certainly like to see that option. I had assumed such a thing would already
exist, and spent quite a while looking for it.

An alternative approach would be "treat this MIME type exactly as you would this
other type", which would be (marginally) more generally useful.

It would probably be unreasonable to attempt to refine it further, to restrict
such mappings to particular domains to cope with (say) a particular JPEG being
presented as an application/octet-stream.

Hugo

I think this should be marked a duplicate of bug 57342.

No, it should not. This bug is specifically aimed at all 'text/*' MIME types,
which should be treated as described in comment 0 and not different from that.

This bug has been reported by Ubuntu users, at
 https://launchpad.net/distros/ubuntu/+source/firefox/+bug/39136

I investigated the code and the fundamental problem seems to be the use of
 mCategoryManager->GetCategoryEntry("Gecko-Content-Viewers",aContentType, )
throughout the code whenever we want to use the Gecko renderer for a type, or check that Gecko can handle it. It's tempting to replace all of these calls with a new function which would do the special handling of unknown text/* types. But I'm not sure that that's correct; in particular, it might make known external text/<something> types malfunction.

So, I'm not sure what needs to be done.

For the avoidance of doubt, I agree 100% with the reporters statement in comment 0, and with Brandon Hall's in comment 9.

Boris Zbarsky's comments that "All the common text/* types that we don't already render as text/plain are not something the user wants to see by default" is missng the point. Sites and applications are free to invent new text/x-* types and RFC2046 says that we should treat those as text/plain if we don't recognise them. Mozilla is never going to be able to have a complete list of these text/* types and it is futile to try. Instead, the logic as required by RFC2046 should be implemented.

(In reply to comment #9)

> be web browsable; however, whenever I try to open links to individual source
> files, an dialog box pops up that wants to open a freaking terminal window so it
> can page the files through less!!

Not really; after I accept, the script text gets appended to .xsession-errors.
Quite funny.

*** Bug 442486 has been marked as a duplicate of this bug. ***

In both Firefox 3.5 and Firefox 3.0, I get prompted to open text/* unknowns in my default text editor. I got the same result in a 3.6 build from a few days ago. Just wanted to poke the bug to see if anyone would like to work on this as it's been over a year since the last comment.

We could show the text along with an infobar that allows opening in a helper app.

*** Bug 1787765 has been marked as a duplicate of this bug. ***

The severity field for this bug is relatively low, S3. However, the bug has 4 duplicates and 16 votes.
:Gijs, could you consider increasing the bug severity?

For more information, please visit [auto_nag documentation](https://wiki.mozilla.org/Release_Management/autonag#severity_underestimated.py).

The last needinfo from me was triggered in error by recent activity on the bug. I'm clearing the needinfo since this is a very old bug and I don't know if it's still relevant.

*** Bug 1841975 has been marked as a duplicate of this bug. ***

@BugBot it is still relevant.

@Boris quote
>text/rtf is the only one I can think of

When I get served "Content-Type: Text/x-php; charset=utf-8" or "Content-Type: Text/x-python; charset=utf-8"
Or similar, I don't want to download it, I want to see it. Then I might press Ctrl+S or Ctrl+A if I actually want to download it.
Chrome and Edge understand this. Firefox doesn't. And that is annoying.