Upload gives AJAX error, HTTP request aborted abnormally

I encountered an identical issue.

A message "ajax","Invalid form POST data." was recorded in dblog.

The same here, clean install of alpha 2.

It's possible my hosting here is to blame, because Drupal 6 didn't work either: now both 7 and 6 work after I created a tmp folder in the directory where Drupal is installed (Drupal is inside a folder and not in the server root).

Has anyone else noticed this to be especially true using Chrome? I get errors in Chrome, but not FF

There is an issue bout these errors. I think they are all (unitl now) caused by providers.
Try to install the website on a localhost, and try again.

Check also php version and stuff like that

Maybe this issue can help #240777: Attach: An HTTP Error 0 occurred (on file upload)

I can reproduce this error reliably, actually it happens all the time, with Chromium browser on Linux 32/64 bit and on Vista with Chrome browser when doing a file (image) upload based on file.module (D7 alpha 5 (and D& CVS HEAD) as it comes "out of the box") and on D6 when using the corresponding CCK (filefield) modules. The file does get uploaded though most of the time, but one gets this huge error message:

An AJAX HTTP request terminated abnormally.
Debugging information follows.
Path: /file/ajax/field_image/und/0/form-ExtTDNqKX5K6Tw9XXswPUvwBWu0NTByBr9v6QSjuJ2w
StatusText: n/a
ResponseText: [{"command":"settings","settings":{"basePath":"\/","overlay":{"paths":{"admin":"node\/*\/edit\nnode\/*\/delete\nnode\/*\/revisions\nnode\/*\/revisions\/*\/revert\nnode\/*\/revisions\/*\/delete\nnode\/add\nnode\/add\/*\nadmin\nadmin\/*\nbatch","non_admin":""},"ajaxCallback":"overlay-ajax"},"ajax":{"edit-field-image-und-0-remove-button":{"wrapper":"edit-field-image-und-0-ajax-wrapper","effect":"none","progress":{"type":"throbber","message":null},"event":"mousedown","keypress":true,"selector":"#edit-field-image-und-0-remove-button","speed":"none","method":"replaceWith","url":"\/file\/ajax\/field_image\/und\/0\/form-ExtTDNqKX5K6Tw9XXswPUvwBWu0NTByBr9v6QSjuJ2w","submit":{"_triggering_element_name":"field_image_und_0_remove_button","_triggering_element_value":"Remove"}}}},"merge":false},{"command":"insert","method":"replaceWith","selector":null,"data":"\u003cdiv id=\"edit-field-image-und-0-ajax-wrapper\"\u003e\u003cdiv class=\"form-item form-type-managed-file form-item-field-image-und-0\"\u003e\n \u003clabel for=\"edit-field-image-und-0\"\u003eImage \u003c\/label\u003e\n \u003cdiv class=\"image-widget form-managed-file clearfix\"\u003e\u003cdiv class=\"image-preview\"\u003e\u003cimg typeof=\"foaf:Image\" src=\"http:\/\/d7t1.hopto.org\/image\/generate\/thumbnail\/public\/field\/image\/Far_far_north_480x270.jpg\" alt=\"\" \/\u003e\u003c\/div\u003e\u003cdiv class=\"image-widget-data\"\u003e\u003cspan class=\"file\"\u003e\u003cimg class=\"file-icon\" alt=\"\" title=\"image\/jpeg\" src=\"\/modules\/file\/icons\/image-x-generic.png\" \/\u003e \u003ca href=\"http:\/\/d7t1.hopto.org\/sites\/default\/files\/field\/image\/Far_far_north_480x270.jpg\" type=\"image\/jpeg; length=42581\"\u003eFar_far_north_480x270.jpg\u003c\/a\u003e\u003c\/span\u003e \u003cspan class=\"file-size\"\u003e(41.58 KB)\u003c\/span\u003e \u003cinput type=\"submit\" name=\"field_image_und_0_remove_button\" id=\"edit-field-image-und-0-remove-button\" value=\"Remove\" class=\"form-submit\" \/\u003e\n\u003cdiv class=\"form-item form-type-textfield form-item-field-image-und-0-alt\"\u003e\n \u003clabel for=\"edit-field-image-und-0-alt\"\u003eAlternate text \u003c\/label\u003e\n \u003cinput type=\"text\" maxlength=\"80\" name=\"field_image[und][0][alt]\" id=\"edit-field-image-und-0-alt\" size=\"60\" value=\"\" class=\"form-text\" \/\u003e\n \u003cdiv class=\"description\"\u003eThis text will be used by screen readers, search engines, or when the image cannot be loaded.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cinput type=\"hidden\" name=\"field_image[und][0][fid]\" id=\"edit-field-image-und-0-fid\" value=\"10\" \/\u003e\n\u003cinput type=\"hidden\" name=\"field_image[und][0][display]\" id=\"edit-field-image-und-0-display\" value=\"1\" \/\u003e\n\u003c\/div\u003e\u003c\/div\u003e\n \u003cdiv class=\"description\"\u003eUpload an image to go with this article.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\u003cspan class=\"ajax-new-content\"\u003e\u003c\/span\u003e","settings":{"basePath":"\/","overlay":{"paths":{"admin":"node\/*\/edit\nnode\/*\/delete\nnode\/*\/revisions\nnode\/*\/revisions\/*\/revert\nnode\/*\/revisions\/*\/delete\nnode\/add\nnode\/add\/*\nadmin\nadmin\/*\nbatch","non_admin":""},"ajaxCallback":"overlay-ajax"},"ajax":{"edit-field-image-und-0-remove-button":{"wrapper":"edit-field-image-und-0-ajax-wrapper","effect":"none","progress":{"type":"throbber","message":null},"event":"mousedown","keypress":true,"selector":"#edit-field-image-und-0-remove-button","speed":"none","method":"replaceWith","url":"\/file\/ajax\/field_image\/und\/0\/form-ExtTDNqKX5K6Tw9XXswPUvwBWu0NTByBr9v6QSjuJ2w","submit":{"_triggering_element_name":"field_image_und_0_remove_button","_triggering_element_value":"Remove"}}}}}] closepinpinsearchzoomoutzoominzoomin
ReadyState: undefined

IMHO: Basically this amounts to D7 file uploads based on AJAX being unusable with Chrome/Chromium browser. Other browsers work fine for me.

I use chrome all the time never get these errors....

Replying to myself in #7: Eventually I found that the Chrome browser extension EzLinkPreview was causing the problem. Disabling the extension fixed the problem.

I'm going to close this as this is a duplicate of #240777: Attach: An HTTP Error 0 occurred (on file upload) in some way.
Feel free to reopen if necessary...

I have this error on drupal, when i use views, i cannot create one view because this error.

Please Help.

An AJAX HTTP request terminated abnormally.
Debugging information follows.
Path: http://aaaaaaa.com/admin/views/ajax/autocomplete/tag
ResponseText:
ReadyState: 4

my website is off-line because this.

Thank,

Paulo

I encountered the same problem and after much frustration found out that I don't get the error if I use Firefox. I only tested it out on Firefox 3.6, IE 8, Opera 11, and Opera 11.1beta. I also noticed I don't have any problems when I'm on a Windows XP machine, just on Windows 7. I have Windows 7 Ultimate, not sure if that matters. It's weird, I used the same versions of browsers and XP has no problems so I can't say for certain if it's really my host to blame. I would really like to know if anyone got to the bottom of this or noticed any other patterns because I need to do something since most of my users are on IE and Windows 7. Although I haven't actually tested it out on other Win 7 machines. Will do more testing and post an update soon.

sub

i'm running Drupal 7.10 on PHP 5.2.17 -- i get this error message when i try to upload an image:

An AJAX HTTP request terminated abnormally.
Debugging information follows.
Path: /?q=file/ajax/field_image/und/form-3F2eSnm6KPiqWLfcTEmPmVbQ0k9Vm4JXg0DPPB0CaIE
StatusText: n/a
ResponseText:
Fatal error: Call to undefined function file_mimetype_mapping() in /home/mangalas/public_html/DRUPAL7/includes/stream_wrappers.inc on line 316
ReadyState: undefined

i'm new to Drupal and at a total loss - can someone please help?

my drupal installation in a subdirectory off root

Hi zopa,

This issue is closed and related to a specific issue. I'd suggest opening a separate issue or creating a forum post. (To help troubleshoot, exact steps to reproduce from "Install Drupal 7.10" would also be a good idea, in that separate post.)

I was also getting this error. What worked for me was the solution suggested here:

I guess I can't post links yet, so go to:
montenasoft(dot)com

and do a search for:
500 internal server error

The post that comes up is the answer (at least for me)

I am getting something similar when clicking "remove" on an uploaded file link (an image). I have tried the same build on 2 other servers and it works fine... But not on the production server!!! The error does not seem to give much indication of what I should do. If anyone has any pointers!!

Type ajax
Date Friday, 27 January 2012 - 7:00am
User administrator
Location http://test.titanblack.co.uk/file/ajax/field_defaultimage/und/0/form-IJU...
Referrer http://test.titanblack.co.uk/node/250/edit
Message Invalid form POST data.
Severity warning

If I check the location this is what is there:

[{"command":"settings","settings":{"basePath":"\/","pathPrefix":"","ajaxPageState":{"theme":"titanblack_zen","theme_token":"HQSKDetrd2Vw8xtSEHZ0cxdePgx1Xofi3AROpe_G9DI","css":[]},"colorbox":{"transition":"elastic","speed":"350","opacity":"0.85","slideshow":false,"slideshowAuto":true,"slideshowSpeed":"2500","slideshowStart":"start slideshow","slideshowStop":"stop slideshow","current":"{current} of {total}","previous":"\u00ab Prev","next":"Next \u00bb","close":"Close","overlayClose":true,"maxWidth":"100%","maxHeight":"100%","initialWidth":"300","initialHeight":"100","fixed":true,"__drupal_alter_by_ref":["none"]},"jcarousel":{"ajaxPath":"\/jcarousel\/ajax\/views"},"nice_menus_options":{"delay":"800","speed":"fast"},"overlay":{"paths":{"admin":"node\/*\/webform\nnode\/*\/webform\/*\nnode\/*\/webform-results\nnode\/*\/webform-results\/*\nnode\/*\/submission\/*\nnode\/*\/clone\nnode\/*\/edit\nnode\/*\/delete\nnode\/*\/revisions\nnode\/*\/revisions\/*\/revert\nnode
\/*\/revisions\/*\/delete\nnode\/add\nnode\/add\/*\noverlay\/dismiss-message\nuser\/*\/shortcuts\nadmin\nadmin\/*\nbatch\ntaxonomy\/term\/*\/edit\nuser\/*\/cancel\nuser\/*\/edit\nuser\/*
\/edit\/*","non_admin":"admin\/structure\/block\/demo\/*\nadmin\/reports\/status\/php"},"ajaxCallback":"overlay-ajax"},"CToolsModal":{"loadingText":"Loading...","closeText":"Close Window","closeImage":"\u003cimg typeof=\"foaf:Image\" src=\"http:\/\/test.titanblack.co.uk\/sites\/all\/modules\/contrib\/ctools\/images\/icon-close-window.png\" alt=\"Close window\" title=\"Close window\" \/\u003e","throbber":"\u003cimg typeof=\"foaf:Image\" src=\"http:\/\/test.titanblack.co.uk\/sites\/all\/modules\/contrib\/ctools\/images\/throbber.gif\" alt=\"Loading\" title=\"Loading...\" \/\u003e"},"modal-popup-small":{"modalSize":{"type":"fixed","width":300,"height":300},"modalOptions":{"opacity":0.7,"background":"#000"},"animation":"fadeIn","modalTheme":"ModalFormsPopup","throbber":"\u003cimg typeof=\"foaf:Image\" src=\"http:\/\/test.titanblack.co.uk\/sites\/all\/modules\/site\/tb_modal_forms\/images\/preload_bar2.gif\" alt=\"Loading...\" title=\"Loading\" \/\u003e","closeText":"Close"},"modal-popup-medium":{"modalSize":{"type":"fixed","width":600,"height":500},"modalOptions":{"opacity":0.7,"background":"#000"},"animation":"fadeIn","modalTheme":"ModalFormsPopup","throbber":"\u003cimg typeof=\"foaf:Image\" src=\"http:\/\/test.titanblack.co.uk\/sites\/all\/modules\/site\/tb_modal_forms\/images\/preload_bar2.gif\" alt=\"Loading...\" title=\"Loading\" \/\u003e","closeText":"Close"},"modal-popup-large":{"modalSize":{"type":"scale","width":0.8,"height":0.8},"modalOptions":{"opacity":0.7,"background":"#000"},"animation":"fadeIn","modalTheme":"ModalFormsPopup","throbber":"\u003cimg typeof=\"foaf:Image\" src=\"http:\/\/test.titanblack.co.uk\/sites\/all\/modules\/site\/tb_modal_forms\/images\/preload_bar2.gif\" alt=\"Loading...\" title=\"Loading\" \/\u003e","closeText":"Close"},"extlink":{"extTarget":"_blank","extClass":"ext","extSubdomains":1,"extExclude":"","extInclude":"","extAlert":0,"extAlertText":"This link will take you to an external web site. We are not responsible for their content.","mailtoClass":"mailto"}},"merge":true},{"command":"insert","method":"replaceWith","selector":null,"data":"\u003cdiv class=\"messages error\"\u003e\n\u003ch2 class=\"element-invisible\"\u003eError message\u003c\/h2\u003e\nAn unrecoverable error occurred. The uploaded file likely exceeded the maximum file size (128 MB) that this server supports.\u003c\/div\u003e\n","settings":null},{"command":"insert","method":"prepend","selector":"head","data":"\u003cstyle media=\"all\"\u003e\n\u003c!--\/*--\u003e\u003c![CDATA[\/*\u003e\u003c!--*\/\n\n\n\/*]]\u003e*\/--\u003e\n\u003c\/style\u003e\n","settings":null}]

I have encountered this error as well. And indeed, there seems to be no solution for this, till I digged a bit deeper.

Probably your PHP runs as FastCGI application. Then probably you are affected by this:
http://httpd.apache.org/mod_fcgid/mod/mod_fcgid.html#fcgidmaxrequestlen

In FastCGI, for some reason, the default value has changed from 1GB to 130kB as you can read on the link above:

Before 2.3.6, this defaulted to 1GB. Most users of earlier versions should use this directive to set a more reasonable limit.

You should have following error in your error.log:
[Thu Feb 09 19:01:04 2012] [warn] [client 81.164.155.215] mod_fcgid: HTTP request length 131860 (so far) exceeds MaxRequestLen (131072), referer: .........

There are 2 ways you can solve this: change FastCGI or make PHP run as apache module. Here I explain how you can change your server configuration.

You should add following to your server config or virtual host config:

<IfModule mod_fcgid.c>
  # 20MB should be enough
  MaxRequestLen 20000000
</IfModule>

You cannot add this to your .htaccess file, so you will need to have access to your server.

Please let me know if this helps.

Thanks TheOptimizer!!

Putting "MaxRequestLen 20000000" in the virtualhost file work perfect.

Using Drupal 7.14.

Worked for me as well! Thanks for the help!

For those still having trouble, make sure to restart your server after changing the file so the changes can take place.

Increasing PHP memory size to allow it to resize large images worked for me. See http://drupal.org/node/372865

For me the issue was related to FastCGI.

Saw this in my server log....
mod_fcgid: HTTP request length 16778734 (so far) exceeds MaxRequestLen (16777216)

I turned off FastCGI using Parallels on my server using the opposite of the instructions here...
http://kb.mediatemple.net/questions/1890/%28dv%29+How+do+I+enable+FastCG...

Hope this helps someone. There is a way to do this with FastCGI still on, but I was having other issues so I decided to turn it off.

For me the problem was solved by changing the value of "max_execution_time" to "0", on the php.ini file.

TheOptimizer #19 was exactly the fix in our case. Thanks, I added this solution to a few of the other posts on this topic http://drupal.org/node/1015938#comment-

#4 worked for me! I loaded it up in FireFox and everything worked 100%!

Thanks for the fix!

@pipep in #24:

I would recommend not doing that.

That means that any request to your site can run indefinitely, which could end up killing your server.

At least set some sort of limit, even if it is large, like 300 (5 minutes) or something.

If someone's connection is too slow to be uploading a file in 5 minutes then it is quite likely they should be using a faster connection or uploading a smaller file (at least in most cases).

solved by changing the value of "max_execution_time" to "0"

Epic. That's like chopping off a leg to fix a broken toe.

This is an old issue, but thought I'd post here since I had almost the identical error in 7.22 recently.

The fix that worked for us was using jQuery Update, WITH the patch from here: https://drupal.org/node/1995790#comment-7553275.

It updated the jquery.form.js and jquery.form.min.js files/versions that jQuery Update uses. Prior to the patch, jQuery Update version 7.x-2.3 alone did not solve the issue -- post patch, it appears to be working.

how i would add this virtual host config in godaddy

<IfModule mod_fcgid.c>
  # 20MB should be enough
  MaxRequestLen 20000000
</IfModule>

#19 explains the problem and the solution very well: if you get the "500 Internal Server Error" (during an update or the installation of Drupal or a module etc.) and you read [date etc...] ... mod_fcgid: HTTP request length ... exceeds MaxRequestLen (...), referer:... in your Apache error log, which was my case, then the solution is most probably #19, thanks to TheOptimizer.
I can only add that while editing your config file (e.g. conf/httpd.conf) be careful to use the same name/alias given for the fcgid module, i.e. if the module is loaded by

...
LoadModule fcgid_module modules/mod_fcgid.so

then you have to add
<IfModule fcgid_module>...
not
<IfModule mod_fcgid.c>...

I tried all of these fixes... MY fix was....

I have a settings.php $base_url WITH the 'www'

Then in .htaccess file (root of folder), I un-commented (removed the hashtag):

RewriteCond %{HTTP_HOST} !^www\. [NC]
RewriteRule ^ http%{ENV:protossl}://www.%{HTTP_HOST}%{REQUEST_URI} [L,R=301]

Error is gone.

Thanks for Drupal community guidance!

@TheOptimizer #19

Solid gold! thanx a million!

For NGINX users....
I was getting the same (or very nearly) error uploading audio files larger than 1MB.
There is a max body parameter that needs to be adjusted in nginx.conf
Details here:
http://jesin.tk/fix-client-intended-to-send-too-large-body-nginx-error/

Short version: find your nginx.conf file.
add or modify the following line inside http {…}
client_max_body_size 20M;

Worked for me.

Just went through a few weeks of trying to fix the exact same issue. In our case, the problem was caused by the Suhosin PHP extension. That extension was limiting GET and POST requests in a way that was breaking almost any Drupal feature using AJAX. Thought I would mention that here in case it helps anyone else.

Ectopod how the hell did you figure this out?????? ive tried everything and finally found your comment after searching for a long time. Thanks so much!!!!!!

The solution in #35 worked for me as well. Thank you.

For me adding this to my mysql config (/etc/my.cnf) file fixed the problem :

max_allowed_packet=16M

Though it may be useful to ensure that your web server, php.ini and other related service configs are also accommodating php request, post size, memory limits, upload size and other related functions.

Thank you Ectopod for your reply. I have a question, what did you do do with Suhosin? disabled it or what?

I just ran into this same issue and found a different solution to this problem.
We are on a share hosting platform with Nexcess.net and it turns out that this was caused by a Mod Security rule being tripped.
I was able to talk to the support team and have them create a mod security exception that allowed image and file attachments via AJAX to work.

# 20MB should be enough
MaxRequestLen 20000000

I added this to my vhost configuration at it did the trick :)

Actually in my case I made it 200MB
so:

MaxRequestLen 200000000

Thanks Smatron #30 - it helped.

Dear Sir,
all you have to do is make the host php version the same as the one on your localhost

#35 worked for me.
Suhosin PHP extension in the PHP settings of my cPanel caused the issue. Disabling (de-selecting) the same resolved the issue.

Thanks.

I have the exact same issue as #18. The only way for me to remove an image is to disable java in the browser. Does anyone know what the issue could be?

The solution for me (proposed by my Upwork freelancer Shikha rani) was to add Header always set X-Frame-Options "sameorigin" in .htaccess

Thank You Garette for giving me credit here. @GarChris :)

Thank you @theoptimizer !!

#29 Oh god! U literally save my ass!I had try all solutions listed above,and it didn't work!Until I med ur solutions!Thanks!

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    <div class="join_our_team gbb-row bg-size-contain"  style="padding-top:100px; background-image:url('/sites/default/files/ginesys/header-bg.svg'); background-repeat:no-repeat; background-position:center top" >
    <div class="bb-inner default">  
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        <div class="row">
          <div class="row-wrapper clearfix">
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                <div class="column-inner  bg-size-cover " >
                  <div class="column-content-inner">
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            <div class="sub-title"><span><a href="career">Careers  > </a>   Join Our Team</span></div>            <h2 class="title"><span>Please Fill Up the form to apply</span></h2>            <div class="heading-line"><span class="one"></span><span class="second"></span><span class="three"></span></div>
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              </div>
                                  <div  class="gsc-column col-lg-1 col-md-1 col-sm-2 col-xs-12">
                <div class="column-inner  bg-size-cover " >
                  <div class="column-content-inner">
                                      </div>  
                                    </div>
              </div>
                                  <div  class="gsc-column col-lg-6 col-md-6 col-sm-12 col-xs-12 contact-message-become-partner-form">
                <div class="column-inner  bg-size-cover " >
                  <div class="column-content-inner">
                    [{"command":"settings","settings":{"ajaxPageState":{"theme":"gavias_edubiz","libraries":"admin_toolbar\/toolbar.tree,admin_toolbar_search\/search,admin_toolbar_tools\/toolbar.icon,contextual\/drupal.contextual-links,contextual\/drupal.contextual-toolbar,core\/drupal.active-link,core\/drupal.collapse,core\/html5shiv,core\/jquery.form,devel\/devel-toolbar,file\/drupal.file,gavias_blockbuilder\/gavias_blockbuilder.assets.frontend,gavias_edubiz\/gavias_edubiz.gallery,gavias_edubiz\/gavias_edubiz.skin.default,gavias_edubiz\/global-styling,gavias_sliderlayer\/gavias_sliderlayer.assets.frontend,gaviasthemer\/customize,history\/mark-as-read,imce\/drupal.imce.filefield,layout_discovery\/onecol,shortcut\/drupal.shortcut,statistics\/drupal.statistics,system\/base,toolbar\/toolbar,toolbar\/toolbar.escapeAdmin,tour\/tour,user\/drupal.user.icons,we_megamenu\/form.we-mega-menu-frontend"},"ajax":{"edit-field-cv-upload-0-remove-button--KXsOFLy4_kU":{"callback":["Drupal\\file\\Element\\ManagedFile","uploadAjaxCallback"],"wrapper":"ajax-wrapper---wefzX9WICg","effect":"none","progress":{"type":"throbber","message":null},"event":"mousedown","keypress":true,"prevent":"click","url":"\/join-our-team?element_parents=field_cv_upload\/widget\/0\u0026ajax_form=1\u0026_wrapper_format=html","dialogType":"ajax","submit":{"_triggering_element_name":"field_cv_upload_0_remove_button","_triggering_element_value":"Remove"}}},"ajaxTrustedUrl":{"\/join-our-team?element_parents=field_cv_upload\/widget\/0\u0026ajax_form=1\u0026_wrapper_format=html":true},"pluralDelimiter":"\u0003","user":{"uid":"1","permissionsHash":"4a9ccb53625a94af1e953e5d66aeba0f0f1bceb1f4cf774eb8213fe1e22d751d"}},"merge":true},{"command":"update_build_id","old":"form-CRcTW81U3Ab_1-2Gnx3QE5dkfinccQ1wXMLr3dqcaBg","new":"form-nBn1ykCKXj72Dex75CGaAF-9hYAz38tgXXQT-q2aIzI"},{"command":"insert","method":"replaceWith","selector":null,"data":"\u003Cdiv id=\u0022ajax-wrapper---wefzX9WICg\u0022\u003E\u003Cdiv class=\u0022js-form-item form-item js-form-type-managed-file form-item-field-cv-upload-0 js-form-item-field-cv-upload-0\u0022\u003E\n      \u003Clabel for=\u0022edit-field-cv-upload-0-upload--_RY_FNuqaDA\u0022 id=\u0022edit-field-cv-upload-0--4Xpw39klU6M--label\u0022\u003ECV Upload\u003C\/label\u003E\n        \u003Cdiv id=\u0022edit-field-cv-upload-0--4Xpw39klU6M\u0022 class=\u0022js-form-managed-file form-managed-file\u0022\u003E\n  \u003Cinput data-drupal-selector=\u0022edit-field-cv-upload-0-fids\u0022 type=\u0022hidden\u0022 name=\u0022field_cv_upload[0][fids]\u0022 value=\u00221468\u0022 \/\u003E\n\u003Cspan data-drupal-selector=\u0022edit-field-cv-upload-0-file-1468-filename\u0022 class=\u0022file file--mime-text-plain file--text\u0022\u003E\u003Ca href=\u0022https:\/\/ginesys.ddev.site\/sites\/default\/files\/2021-05\/2021_04_15_06_57_57_bb_export_30.txt\u0022 type=\u0022text\/plain; length=21328\u0022\u003E2021_04_15_06_57_57_bb_export_30.txt\u003C\/a\u003E\u003C\/span\u003E\n\u003Cdiv class=\u0022js-form-item form-item js-form-type-checkbox form-item-field-cv-upload-0-display js-form-item-field-cv-upload-0-display\u0022\u003E\n        \u003Cinput class=\u0022file-display form-checkbox\u0022 data-drupal-selector=\u0022edit-field-cv-upload-0-display\u0022 type=\u0022checkbox\u0022 id=\u0022edit-field-cv-upload-0-display--tJNxaJLlGAg\u0022 name=\u0022field_cv_upload[0][display]\u0022 value=\u00221\u0022 checked=\u0022checked\u0022 \/\u003E\n\n        \u003Clabel for=\u0022edit-field-cv-upload-0-display--tJNxaJLlGAg\u0022 class=\u0022option\u0022\u003EInclude file in display\u003C\/label\u003E\n      \u003C\/div\u003E\n\u003Cinput data-drupal-selector=\u0022edit-field-cv-upload-0-remove-button\u0022 formnovalidate=\u0022formnovalidate\u0022 type=\u0022submit\u0022 id=\u0022edit-field-cv-upload-0-remove-button--KXsOFLy4_kU\u0022 name=\u0022field_cv_upload_0_remove_button\u0022 value=\u0022Remove\u0022 class=\u0022button js-form-submit form-submit\u0022 \/\u003E\n\n\u003C\/div\u003E\n\n        \u003C\/div\u003E\n\u003C\/div\u003E\u003Cspan class=\u0022ajax-new-content\u0022\u003E\u003C\/span\u003E","settings":null}]

I have this crazy HTML getting added to my response header which causes parseerror, anybody got any idea what could be causing this, what functions and stuff should I be looking for? it only happens with a certain page not with other forms with file upload!

#29 solved it for me. Thank you, @pjbarry21 !!
(Though of course it's been 9 years since the original post, so we can just update the jQuery Update plugin normally, and don't need to apply any special patches anymore.)