XML Parsing Errors Topic is solved

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moonbob69
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XML Parsing Errors

Unread post by moonbob69 » 2021-03-15, 10:17

Since I last accessed it 1+ yrs ago when it worked with earlier PM, the site DriveHQ.com with PM 28.16.0 now gives XML Parsing Error preventing login. A week ago, it was because the <title> contained a raw ampersand character in violation of html rules. The DriveHQ tech staff said no one else had ever made a complaint, and that it was actually PM's problem, as there was some loophole for ampersand's followed by a space that other browsers recognized. Hence the category of this report.

They finally did give in and replace it with &amp, I see by viewing source. But I got a different XML Parsing Error about 10 lines later in the body, about something not found in the line <script async src="https://www.googletagmanager.com/gtag/j ... 1068036330">.

Then upon reload minutes later, the full site with no error preventing loading (but 10 ConstraintErrors in the Error Console).

Then upon reload again, the Parsing Error: not well-formed is back, pointing to that bare ampersand character in the title again. Further reloads in subsequent minutes give the same thing, until after maybe 20 minutes, the full site is back again. But clicking "page source" gives a page with the bare ampersand, not the &amp which was there earlier, and which should have displayed an error. Is "page source" reloading from the server instead of displaying the source being rendered?

1. Is there something about PM that detects more XML Parsing Errors than other browsers?
2. Their cloud configuration retrieves different pages at different times; acceptable/normal?
3. I have 3 windows titled Source of [the same site] that are different. Any way to tell them apart or display their download timestamp?

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Re: XML Parsing Errors

Unread post by Moonchild » 2021-03-15, 13:11

Not sure what's supposed to be wrong - i checked just now and everything seems to be fine. Since you were seeing these changing pages they were obviously working on the live server at the time of your checking.
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Re: XML Parsing Errors

Unread post by The Squash » 2021-03-15, 23:54

moonbob69 wrote:
2021-03-15, 10:17
PM 28.16.0
Off-topic:
Consider an upgrade to 29.1.0. If you haven't upgraded because 28.17.0 didn't support 32-bit systems, think again: Steve Pusser's got 32-bit builds still (although that's only helpful on Debian really).

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Re: XML Parsing Errors

Unread post by moonbob69 » 2021-03-16, 19:55

I just checked drivehq.com (4pm EDT) (reloaded twice) and it's back to XML Error for the bare ampersand at Line Number 13, Column 54, making the site unavailable.

Are they correct that there should be an exception for ampersands followed by a space?
Since they fixed it once, is there a problem that some browsers don't process &amp?

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Re: XML Parsing Errors

Unread post by Moonchild » 2021-03-16, 21:09

I'm not even sure why you're getting XML errors since the page itself isn't XML.
I've also tried again and don't see any problems no matter how often I reload.
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Re: XML Parsing Errors

Unread post by Kris_88 » 2021-03-16, 22:40

moonbob69 wrote:
2021-03-16, 19:55
I just checked drivehq.com (4pm EDT) (reloaded twice) and it's back to XML Error for the bare ampersand at Line Number 13, Column 54, making the site unavailable.
In this situation, I would try a fresh profile or at least clear the cache2 and startupCache folders.

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Re: XML Parsing Errors

Unread post by moonbob69 » 2021-03-17, 22:30

Moonchild wrote:
2021-03-16, 21:09
I've also tried again and don't see any problems
Could you look at the page source and see if the page title has the bare ampersand?
ie, only in PM 28.16.0 does this trigger a fatal XML error.

I can also see how with distributed cloud servers, certain IP's might always get a certain batch of servers. Today, its the same XML Error for me.
Kris_88 wrote:
2021-03-16, 22:40
clear the cache2 and startupCache folders.
A brief look at Tools and Help doesn't show how to do that. I would be interested in knowing where those are and how to view what is saved in them. [useful feature: how to "bookmark" a page permanently in cache, so it is available with no internet connection.]

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Re: XML Parsing Errors

Unread post by Kris_88 » 2021-03-17, 22:51

Go to about:profiles page, then find "Local Directory" and press "Open folder".
I have a suspicion that you have damaged startupCache (and/or cache2).
And you should close the browser before cleaning the folders.

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Re: XML Parsing Errors

Unread post by moonbob69 » 2021-03-17, 23:27

Kris_88 wrote:
2021-03-17, 22:51
I have a suspicion that you have damaged startupCache (and/or cache2).
Deleted them, no change upon starting PM again.

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Re: XML Parsing Errors

Unread post by Kris_88 » 2021-03-17, 23:41

Then I have no idea.
I apologize...

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Re: XML Parsing Errors

Unread post by Moonchild » 2021-03-18, 00:22

moonbob69 wrote:
2021-03-17, 22:30
Could you look at the page source and see if the page title has the bare ampersand?
ie, only in PM 28.16.0 does this trigger a fatal XML error.

Code: Select all

<title>DriveHQ Cloud File Server, Drive Mapping & Free FTP Hosting with best customer support. Complete Enterprise Cloud IT & Online File Storage, Backup, Sharing, Sync and WebDAV services</title>
There is an unescaped & there but that does not trigger an error.

EDIT: I actually looked up the HTML spec and bare ampersand in title is perfectly fine according to the spec.
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Re: XML Parsing Errors

Unread post by jobbautista9 » 2021-03-18, 04:05

I just downloaded a 28.16.0 Linux binary from archive.palemoon.org and accessed drivehq.com on 12pm PHT. Made an account, tried login. Both works fine.

Something must be causing your profile to trigger XML serialisation mode for HTML5. Could be an extension?

Please provide troubleshooting info.
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Re: XML Parsing Errors

Unread post by moonbob69 » 2021-03-18, 08:53

jobbautista9 wrote:
2021-03-18, 04:05
Could be an extension? Please provide troubleshooting info.
No extensions or plugins I am aware of. When looking at Help, I found "Troubleshootiing Info" which I will try to attach instead of pasting here; I didn't see anything that sounded like "serialisation mode".
I guess you already know where that "XML Parsing" message comes from.

"If you wish to attach one or more files enter the details below. You may also attach files by dragging and dropping them in the message box." Didn't seem to work. Dragging to edit box did nothing, drag to "add files" under "attachments" in Post Reply tab replaced that tab with the local file opened in PM.
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Re: XML Parsing Errors

Unread post by Moonchild » 2021-03-18, 09:15

moonbob69 wrote:
2021-03-18, 08:53
I guess you already know where that "XML Parsing" message comes from.
No, we don't.
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Re: XML Parsing Errors

Unread post by moonbob69 » 2021-03-21, 09:11

Isn't "XML serialisation mode" a known section of code? Back when I was doing C code, one could always just search for error messages like "Parsing Error" and "not well-formed" in the source code. Even if all the messages were in one place, you would get the offset for that phrase and then search for that address.

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Re: XML Parsing Errors

Unread post by Moonchild » 2021-03-21, 09:21

We know where XML is parsed in the tree of course, but that doesn't help. The XML parser isn't our only parser. We have 2 HTML parsers, parsers for MathML, CSS, JS, SVG, JSON, etc. All of that code is only called on when certain content is detected.
So short of being able to reproduce ourselves which I haven't been able to, we at the very least need the exact XML parsing error you get with indication of the error and where it happens in what file.
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Re: XML Parsing Errors

Unread post by moonbob69 » 2021-03-22, 20:46

The Error Console only says what is shown on the screen:
"XML Parsing Error: not well-formed Location: https://www.drivehq.com/ Line Number 13, Column 54:
<title>DriveHQ Cloud File Server, Drive Mapping & Free FTP Hosting with best customer support. Complete Enterprise Cloud IT & Online File Storage, Backup, Sharing, Sync and WebDAV services</title>
-----------------------------------------------------^" [where this points to the blank after the ampersand]

The "Page Information" has its own bug: you can only select the words "Untitled Page", and as a pop-up, you can't get to options to get around that. (suggestion: for all pop-up windows, a hidden command that will make the window a regular one with the regular options.)

But Page Information does say that the error msg page is Type: application/xhtml+xml, and Render Mode:
Standards compliance mode, Encoding: UTF-8.

What more can be found?

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Re: XML Parsing Errors

Unread post by vannilla » 2021-03-22, 20:55

It appears to be that the document being served is plain old HTML, but the server sends a Content-Type header stating the content is actually XHTML.
The browser trusts the header and tries to parse the document as XML, I suppose.
You might want to shoot a mail to the drivehq developers telling them to change the header to text/html.

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Re: XML Parsing Errors

Unread post by New Tobin Paradigm » 2021-03-22, 21:19

I can't reproduce the issue but maybe it is something with a content modifying extension.

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Re: XML Parsing Errors

Unread post by vannilla » 2021-03-22, 21:35

Found the issue: it's a user agent sniffing issue.
I normally browse using the "Native" setting for the user agent compatibility preference and that triggers a Content-Type of application/xhtml+xml.
Setting it to "Firefox compatibility" makes the server send the text/html Content-Type header.
In both cases the served document is the same, it's just the value of the header to change.

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