This is the message from the error log (/var/log/apache2/error_log):
[Tue Sep 02 12:24:44.772454 2025] [php:error] [pid 625722:tid 625722] [client 108.161.129.198:48784] PHP Fatal error: Declaration of Dhii\Container\ProxyContainer::has($key) must be compatible with Psr\Container\ContainerInterface::has(string $id): bool in /var/www/countryrobot/wordpress/wp-content/plugins/zettle-pos-integration/vendor/dhii/containers/src/ProxyContainer.php on line 50
Hello @robertpheller
To proceed, please try the following steps:
- Download and install this release candidate version: https://drive.google.com/uc?id=1RoOXsE3Qlh4JhYtlGp1fmheRu0aV-8bH
- Upload and activate it from Plugins > Add New > Upload Plugin.
- If your site still crashes, disable all plugins except WooCommerce and Zettle, then activate the plugin again. If successful, reactivate your other plugins one by one to check if any specific one is causing the conflict.
Let us know which plugin triggers the crash, if any. Also, please follow these steps to share your system status report with us:
- Navigate to the
WooCommerce / Status section in your site’s admin panel.
- Click on the
Get system report button and then click Copy for support.
- Paste the report into our PrivateBin.
- After uploading, please share the link here so we can review the details thoroughly.
Looking forward to your response.
Kind Regards,
Krystian
The plugin won’t activate: “Plugin could not be activated because it triggered a fatal error.”
OK, it works will all my plugins except BackWPup.
Hello @robertpheller
I have already created an internal issue for this so the development team can review it. Once it is fixed and included in a release, I will let you know right away.
In the meantime, the only workaround is to avoid running both plugins together.
Kind Regards,
Krystian
Has there been any progress on this issue?
Hello @robertpheller
Thanks for checking in.
We have prepared an updated build that should address the issue. You can download it here: https://drive.google.com/uc?id=1ysP6laP3Fh_oG1KhPvbEtgOMMIB6MRgX
Please install this version and let us know if it resolves the problem. Once confirmed, we’ll include the fix in the next public release.
Kind Regards,
Krystian
Hello @robertpheller
Please share the fatal error details that appear after installing the package. You can upload the error log/stack trace to PrivateBin and share the link with us so we can review it.
Once we have the exact error output, we’ll identify where it fails.
Kind Regards,
Krystian
Hello @robertpheller
Thanks for sharing the link. If you installed the file as provided, it will appear as a separate plugin rather than replacing the existing one. To avoid conflicts, you likely need to deactivate the old Zettle plugin first before activating this new build. The file itself is fully scoped, so once activated independently, it should not trigger the same error you experienced earlier.
Please try that setup and let me know if the issue persists.
Kind Regards,
Krystian
OK, things have been working fine with 1.6.1+izet-335-new-build-wf.1724d25 — when will the next scheduled update come out?
Still waiting on the next scheduled update….
Still waiting on the next scheduled update… Is this plugin still being maintained?
Hello @robertpheller
Yes, the plugin is still actively maintained. We are not planning any significant feature updates in Q1 2026. The bigger changes and improvements are planned for Q2 and Q3 2026.
In the meantime, you are currently running the version that resolved the issue on your site – correct me if I’m wrong? I know it’s not an ideal scenario to run an unofficial package, but it shouldn’t create any problems.
Kind Regards,
Krystian
