New Thunderbird Plug in - want to contribute to its creation?

It seems that Opacus has gone for good. I’ve tried as have others, to contact them for support and th enew working version, only to be unanswered.

I am exploring the option to create a new plug in, with similar features to the Opacus one. Maybe there are more features that might be useful that I have not seen or thought of.

Are you interested in contributing to it?

There would be the up front costs, but then the maintenance for improvements and fixes when it breaks.

If this works out, maybe we can come up with a longer term plan to keep it alive.

Please contact if interested.


If they’ve completely lost interest in maintaining, ideally we could convince them to open-source it. It really makes more sense than starting from scratch…

Hi there.

Your idea makes sense.

I’ve tried many times to get help with no answer. But, I was asking for help with their products.

Maybe asking them to open source it, they might answer.

Let’s see the interested here, and we can maybe look at both angles. Build new, and upgrade the exisiting.



Any update on any of this. Im currently migrating my SugarCRM into SuiteCRM and I am look for CalDav integration.

I’m not a coder by trade, but I can do back-end administrative stuff. I would like to see some kind of integration with CalDav and CardDav. Both these solutions work great and I am using both with Thunderbird.

HI there.

I inquired in to having a plug in developped. But, cost is very high. If 30-40 peopel chipped in, it woudl be less than $50 a piece.
But, no updates…

It would be better to find a developer to work with, and we all put a bit of money in escrow, or in a patreon like system in order to have them develop it, and update it.

I’ve trued contacting the developers of opacus on multiple occasions. It seems dead. Some one suggested making it open source. That’d be ideal, and then we could find a developer to maintain it.

Get back if you have any ideas.s


the plugin is open source, at least the “standard extension” which can be found here:

You will find “license.txt” containing the GPL license, as well as, stating
“Official Opacus standard extension, as released under the GPL in 2010.”

The package contains images, dtd files, javascript files and xul, all perfectly readable.

Hello Jansiero

Thanks for the feedback and information.

You talk abtou readme file and a license txt.

Sorry for looking like I do nto understand, because I’ve only just used Thunderbird to install the plug in. I’ve not looked inside anytime to try and read it.

Where to I find these files? I’d like to file sthese files that are, as you say, open source, and see what we can maybe do with them.


Hi @joehogan,

You can simply download the .xpi file from the link in my last post and save it. It will have the name:

This .xpi is actually a zip file you can extract:

They also published their code for the standard extension in github:

PS: according to this comment from an opacus developer on Dec. 17th 2020 opacus is not gone for good:


I wrote to them directly at least 5-6 times and posted multiple postings to these forums last years.

None of them led a a reply. If what they said is true, they should have:
1 - turned off their system that kept taking payments with out offering a working key.
2 - told everyone what was happening.

I gave up last fall trying to get news from them. It was not for a lack of trying. Their lack of communication towards their clients was a major blunder, in my eyes.

It is 5 months after they wrote that message you showed us. No news since.

Time will tell . They used to call this kind of thing vaporware. I’d love to see this come to the light of day, bu tmy SuiteCRM has dropped to almost 0 since it stopped working(pro and regular)

Getting development of CalDav funded is a great Idea. I’m not sure Patreon would be the right platform for this since Patreon seems designed for already established projects. Probably something like Kickstarter would be better. With Kickstarter we would somehow need to get the word out that it’s happening to interested parties to make it worth doing IMHO. Maybe reaching out to companies that already use SuiteCRM and would benefit from Caldav Integration.

It would be nice to see if there is more support for this then just us two, as I dont see who else would be interested in doing this. But I am willing to put some time into finding out. Is there are list of establishments that use SuiteCRM that I could look at and determine if they would benefit from this development? I would then reach out to them by email to gauge the level of interest in contributing. Then if there is enough interest I could start some kind of crowd source campaign. Does anyone know of any platforms for bounties for code development rather than bugs? It seems like that would be the way to go IMHO.