"Missing Plug-in" when inserting image into Mail Signature

JJGraphics wrote:

I have just had to have my Mac reformatted by the Genius Bar to resolve issues. Now hen I try to insert an image into a Signature in Mail it shows the text

but the image is replaced by a grey block with the "Missing Plug-in" message.

I have previously used this signature with the image on this machine when it had previously been updated to Sonoma from Ventura.

Anyone any ideas on this?

Mac Mini/Sonoma 14.0

https://discussions.apple.com/content/attachment/bfcb5d1e-21de-4780-a2d0-a28c4230c0d7

You do not say why you had to have your Drive reformatted(?) is there a bigger issue...

Not sure the relevance of the screenshot...

where is the message?

I see now your SS was so tiny I could not read it

Note—None of my 5 signature w/ images have been affected by the Sonoma upgrade...

What I can say— Plug-ins are no longer supported in macOS Sonoma.

The new way is "Extensions" see: Mail>Settings>Extensions

—Delete/ Remove/uninstall any old Plug-ins

—If there is a third party involved look for an update there.

Delete the old signatures and build them back new and compare your results.

ref: Create and use email signatures in Mail on Mac - Apple Support

SOLVED - (with a work around)

I received a new MBA M2 15" this week, great machine, superb OS (been away from MacOS since 2015, skipped the dreaded paper thin keyboards. Now, I'm back to the ⌘ world). With this, I had to mime my mail signatures (Linux user since 2010) and faced this "missing plug-in" situation.

MacOS: 14.1.2 (23B92)

Mail App: Version 16.0 (3774.200.91.1.1)

Steps:

1. Use whatever other mail system you have to send you a message with the signature;
2. Access your e-mail from iCloud web - use Safari, preferably;
3. Select the signature from the web iCloud, copy it to the clipboard;
4. In the Mac Mail app, paste it into the signature. Done;

My signature is composed as a

<div>
  <div style my logo and stuff>
    <img alt="alternative text, sure, why not?"
      src="data:image/png;base64,here is the base64 version of the image..." />
  </div>
  <div style"display: inline; float: left; and other little stuff;">
    <div style="font-weight: bold;">My Name</div>
    +55 (11) My Phone Number
    </div>
  </div>
</div>

You get the drill. The reason why I embed the image is so the recipient can be presented my logo even if remote images are disabled (I turn them all off, so I understand who else does that too).

This is a bit more unusual scenario, because the embedded image, so I thought I could share it especially because it is working.

HTH

Same problem. Tried .png and .jpg files but nothing worked. Always got "missing plugin". Then I tried re-starting the mail app and that did the trick. Interestingly, once it was working I was experimenting with various image files and after about 4 or 5, it stopped working again (same "missing plugin"). So I restarted the app and, once again, it started working. I find that once I get the image into the signature, I don't have this problem when using the signature (at least not yet :-) ). Definitely a software bug. I am running Sanoma 14.2.1 on a 2024 MacBook Pro.

I've had this same issue where the inserted image shows as "missing plug in" under Settings>Signatures.

Although oddly when you create an actual email and insert the signature the image inserted shows perfectly!

For me it seems like the images aren't showing under Settings>Signatures for some reason, but otherwise show fine.

P.

Just a follow up to this problem. I too had the error showing "Missing Plug-in" even though the image still appeared in my mail signatures. After updating to Sonoma 14.3 yesterday, I see now that the error message is gone and the image is now showing properly in the Mail Signature setup box.

Can confirm Randall_2023! Same here issue is now resolved with the latest update to Sonoma 14.3

This problem was fixed in Sonoma 14.3.1

I had the same problem.

After creating the signatures with the image/logo, I closed Mail and reopened it, and the signature worked just fine: the logo was there

updating to Somona 14.4 fixed the problem

After up dating to Somona 14.4 all working as before - no other action required

Same issue -- shift-Mail didn't work, Safe Mode didn't work, still receive "missing plug-in" error when trying to add a graphic to a signature. Apple support had me try it using a test account -- and it worked there, I was able to add the graphic to a signature. So it appears to be account specific, but how to fix it, I have no idea.