Remove "Decrypt image.png (123 KB)" text.

[kevincox]

Description

Right now when you send or receive a message on element-web it shows "Decrypt image.png (123 KB)" if you click this it decrypts the image and you can click again to download/view. In my opinion this is a pointless feature.

• As a user I don't care that it needs to be decrypted first.
• I can already right-click the image to save/copy/view like every other site.
• Most users don't care how big the image is. (I've already downloaded it anyways).
• Clicking the image shows this information anyways, when the context makes sense.

Steps to reproduce

• Go to an e2e chat room.
• Send an image.

Version information

• Platform: web

For the web app:

• Browser: Firefox
• OS: NixOS Linux
• URL: app.element.io

[t3chguy]

This is a technical limitation of the Decryption being done asynchronously (and via a sandbox) and a lot of browsers forbidding downloads from triggering a download after such an event, only allowing it as a result of a direct user interaction, hence the need for a 2nd click. On Chrome I don't tend to need to click twice, clicking Decrypt automatically triggers a download, Firefox tends to be stricter

[kevincox]

My point is that this link seems completely unnecessary. Users can already right-click to save like every other image in their browser or they can click the image and use the download button there. To me this link as a whole is just cluttering the chat log, whether you need to click once or twice.

[t3chguy]

Two of your points are misguided, the image shown in the timeline will be just a thumbnail, you clicking decrypt/download is regarding the full-size one.

[kevincox]

Hmm, this does seem to be the case for non-encrypted rooms. For encrypted rooms it will be the full image because there is no server to thumbnail it anyways. It could be removed for encrypted rooms, but it would be too confusing if the UI differs.

Another option is that since the full image is available we should be able to generate the link upfront. But that isn't as good as removing it entirely.

[t3chguy]

The client (sender) can generate a thumbnail along with a source file.
Element Web does make use of this.

Example event containing both source image and thumbnail:

{
  "type": "m.room.message",
  "content": {
    "body": "image.png",
    "info": {
      "size": 3444873,
      "mimetype": "image/png",
      "thumbnail_info": {
        "w": 337,
        "h": 600,
        "mimetype": "image/png",
        "size": 413638
      },
      "w": 901,
      "h": 1600,
      "thumbnail_file": {
        "v": "v2",
        "key": {
          "alg": "A256CTR",
          "ext": true,
          "k": "...",
          "key_ops": [
            "encrypt",
            "decrypt"
          ],
          "kty": "oct"
        },
        "iv": "...",
        "hashes": {
          "sha256": "..."
        },
        "url": "mxc://riot.ovh/eeMYMwRWeEDlBXYSqyUyLKGH",
        "mimetype": "image/png"
      }
    },
    "msgtype": "m.image",
    "file": {
      "v": "v2",
      "key": {
        "alg": "A256CTR",
        "ext": true,
        "k": "...",
        "key_ops": [
          "encrypt",
          "decrypt"
        ],
        "kty": "oct"
      },
      "iv": "...",
      "hashes": {
        "sha256": "..."
      },
      "url": "mxc://riot.ovh/jOkMmIeFlQVYAeBuKNFRTJFD",
      "mimetype": "image/png"
    }
  }
}

[t3chguy]

Its also a useful button for Element Desktop which doesn't have a right click save-as

[kevincox]

Ok, sounds like there are more use cases for this button than it seems. I think it still may be ideal to make it less obvious (such as relying on the download button after click) but it isn't as clear of an improvement as it seemed. I'll close this for now.

It is worth noting that most other messaging apps make the download option far less obvious I can only assume this is based on use metrics of how often that is used vs the noise on screen.