Plugin Advanced Rich Text Editor (Vuram) Converting Images to Base64 that Return an Access Denied Error on the Site

Hello everyone, 
Thank you in advance for your time, me and my team are having some problems with the Advanced Rich Text Editor plugin and pasting images:

Error introduction:

• We are facing some errors related to the use of the plugin Advanced Rich Text Editor (Vuram) (Appian Community)
• We believe this is due to the automatically generated base64 by the plugin when we paste the images.
• On large images this base64 can’t be displayed in the site and is resulting in a weird 403 Access Denied error :
• 
• It seems that there is also a conflict with the a!startProcessLink component, please find more details in the Error details topic

Quick context:

• We use the plugin’s richTextEditorField so that our users can write more personalized emails, attach images to the email’s body and send them directly from the Appian application.
• We then save the generated html in our database and use the Microsoft MS Graph public library and respective Appian marketplace plugins to send the emails (This latest plugin is not so relevant for the case)
• We show the sent/received emails in the Appian application by querying the database, gathering the html and showing it back in the richTextEditorField

Important notes:

• Appian current version is 24.3
• Plugin version is 1.5.2
  On Appian version 24.2 we didn’t notice any of these problems and it seems that the plugin wasn’t automatically generating this base64 and was instead keeping an environment url (axaqas1.appiancloud.com/…)
• On plugin version 1.7.1 we can’t paste images inside the richTextEditorField and have a message saying “Saving image to appian.” Displayed bellow the component:
• 
• When we got the update to Appian 24.2 we also got other problems related to this plugin and the display of images, that were described in other support tickets. (Because of this we are planing a rollback to version 24.2)

Error details

When pasting an image inside the plugin’s richTextEditorField it is automatically generating a base64 as a source to that image. Here we can see the images pasted and text written, and can save the generated html in the database.

This base64 is sometimes really large (we had tests with base64 codes bigger than 200k characters on large images), resulting in an access denied error when we try to display the generated html back in Appian.

This error only occurs on the site, if we use the appian designer we can see the images without any errors either when saving the html or when displaying the html.

We have to select the email we want to display in a grid to be able to see it’s body displayed in another interface, sometimes we can open the email on the first selection and see it’s body, but if we unselect the same row and select it again it displays the access denied error.

On other cases we always get the error (with bigger or multiple images saved on the html), and on other cases it seems to work fine (without images and/or with smaller images).

This error also seems to be related to the a!startProcessLink. If we remove the a!startProcessLinks from the same interface (or child interfaces) of the richTextEditorField we don’t get that error anymore.

Even just by having an empty function like “a!startProcessLink()” without any parameters, together with a base64 is enough to get that error when trying to display the html.

The error only happens when we have these two factors (base64 and a!startProcessLink) and overall seems like a memory/cache issue.

Other notes:

We have checked the permissions and security for all related objects and tested with admin users.

The images sent by email also seem to be cut, showing only a part of it in outlook:

But when decoding the sent base64 we can see the full images:

We have talked directly to the Appian Support but without much help. They have applied some patches that didn't fixed the issue and advised us to try to talk to the community and to the plugin authors (which I'm not being able to do)