Mail: Email Body Images not displayed

[MattSpec]

Expected behavior

Tell us what should happen
mail messages loaded, images displayed after clicking 'show images' button

Actual behavior

Tell us what happens instead
no images are loaded in email body.

Mail app

Mail app version: (see apps admin page, e.g. 0.5.3)
0.14.0
Mailserver or service: (e.g. Outlook, Yahoo, Gmail, Exchange,...)
xo2.x10hosting.com - x10hosting mail - imap

Server configuration

Operating system: (e.g. Debian 8)
kubuntu
Web server: (e.g. Apache, Nginx,...)
Apache
Database: (e.g. MariaDB, SQLite or PostgreSQL)
MariaDB
PHP version: (e.g. 7.0)
7.2
Nextcloud Version: (see admin page, e.g. 13.0.2)
16.0.0

Client configuration

Browser: (e.g. Firefox 48)
Chrome

My Server

Webo.hosting shared instance

[bd8392]

Same Error here...

[temesinko]

Eventually this is the same error like I found. Therefore I won't create a new issue, but share some detailed information:

Client side (after click on "show images")

Internal Server Error (500) when calling URL https://REDACTED/apps/mail/proxy?src=REDACTED&requesttoken=REDACTED

Server side (Nextcloud log)

TypeError: Argument 1 passed to OCA\Mail\Controller\ProxyController::proxy() must be of the type string, null given, called in /var/www/vhosts/REDACTED/lib/private/AppFramework/Http/Dispatcher.php on line 166
/var/www/vhosts/REDACTED/lib/private/AppFramework/Http/Dispatcher.php - line 166:OCA\Mail\Controller\ProxyController->proxy(null)
/var/www/vhosts/REDACTED/lib/private/AppFramework/Http/Dispatcher.php - line 99:OC\AppFramework\Http\Dispatcher->executeController(OCA\Mail\Con ... {}, "proxy")
/var/www/vhosts/REDACTED/lib/private/AppFramework/App.php - line 126:OC\AppFramework\Http\Dispatcher->dispatch(OCA\Mail\Con ... {}, "proxy")
/var/www/vhosts/REDACTED/lib/private/AppFramework/Routing/RouteActionHandler.php - line 47:OC\AppFramework\App::main("OCA\\Mail\\ ... r", "proxy", OC\AppFramew ... {}, { _route: "mail.proxy.proxy"})
<<closure>>OC\AppFramework\Routing\RouteActionHandler->__invoke({ _route: "mail.proxy.proxy"})
/var/www/vhosts/REDACTED/lib/private/Route/Router.php - line 297:call_user_func(OC\AppFramew ... {}, { _route: "mail.proxy.proxy"})
/var/www/vhosts/REDACTED/lib/base.php - line 975:OC\Route\Router->match("/apps/mail/proxy")
/var/www/vhosts/REDACTED/index.php - line 42:OC::handleRequest()

[bd8392]

Was anyone able to resolve the issue? I have normal theme and the same appears...

[Nikhos]

I've got this Error, too.
NC 16.0.1
Mail 0.15.1

[ChristophWurst]

At least on @temesinko's instance it's strange that the src URL parameter is not passed into Nextcloud. Do you have any URL rewriting in place? Is there a reverse proxy in front of your Nextcloud?

[bd8392]

I have traefik in place...

[temesinko]

At least on @temesinko's instance it's strange that the src URL parameter is not passed into Nextcloud. Do you have any URL rewriting in place? Is there a reverse proxy in front of your Nextcloud?

I'm using Plesk with Nextcloud running on Apache with nginx in proxy mode in front of it.

[ChristophWurst]

Okay, then please make sure your proxies do not remove the parameter.

[ChristophWurst]

Dup of https://github.com/nextcloud/mail/issues/1341#issuecomment-493894749

[temesinko]

I can verify that disabling nginx completely does not fix the issue.

[MattSpec]

I've been trying to find an error message anywhere. There just doesn't seem to be one. When I click on show images I see them all coming in to the browser with 200 but they're not displayed on the page.

[Lawkss]

I have the same problem.

I disabled the official Mail App and use AfterLogic Webmail. No problems with images in html mail.

[ChristophWurst]

I disabled the official Mail App and use AfterLogic Webmail. No problems with images in html mail.

Thank you for your comment. I'm sure a lot of users in this thread will benefit from this solution.

[JensKillermann]

same problem. AfterLogic Webmail isn't an alternative for me.

[ChristophWurst]

AfterLogic Webmail isn't an alternative for me.

my other comment was meant to be sarcastic :)

[bd8392]

Issue persists... don't see that traefik removes any parameters...

[temesinko]

In the meantime I migrated my Nextcloud from a Plesk subscription (nginx in front of Apache) to it's own VM on a Proxmox host. At this moment it is using no reverse web proxy in front of Apache but the issue still persists. With nginx I had errors with status 500, now I get status 200 but with empty response data. Running on: Apache 2.4 with PHP 7.3 FPM
I'll have a look into the server logs asap.

[charlessteiner]

I have the same issue on two centos 7 setups (apache, php 7.1 & php 7.2, current nextcloud and mail) no proxies. I've tried with two email providers: namecheap and self hosted mail-in-a-box.

Anyone have luck?

[user7466]

I see this problem also, on my setup what is happening is that the images are downloaded ok, but the img tag in the html has style="display:none;" set. If I toggle that off in dev console the image displays.
Currently poking around to find out why...

[user7466]

It is line 76 in lib/Service/HtmlPurify/TransformImageSrc.php that is setting it to none:
$attr = $this->setDisplayNone($attr);

js event onShowBlockedContent() is not explicitly removing display:none
It is, however, replacing style with data-original-style, but TransformImageSrc does not set that.

This can be fixed by either not hiding blocked images at all in TransformImageSrc or by getting it to set data-original-style:
$attr['data-original-style'] = $attr['style'];

[user7466]

This is on nextcloud 17 btw. I can't work out how it is could be working for some people and not others

[JensKillermann]

great, it works. Testet with nextcloud 17

[autoize]

Great comment @user7466.
Commenting out line 76 $attr = $this->setDisplayNone($attr); in $nextcloud_dir/apps/mail//lib/Service/HtmlPurify/TransformImageSrc.php, disabling, then reenabling the Mail app resolves the problem with allowing images in NextCloud 17.0.