I have "key exchange was not successful" with keepass 2.4.3 on Linux Mint 18.3 Sylvia and Firefox 67.0.4. Connect button does nothing. What should I do?

P.S. I don't have this problem with 2.4.3 on Linux Mint 19.1 Tessa and Firefox 66.0.1.

Manjaro OS.
I have just reinstalled this add-on and keep receiving the same nag error in the add-on window.
Browser integration in KeepassXC is enabled, add-on is configured and connected to KeepassXC but add-on window keeps returning that I am using an old version of KeepassXC.
I installed the add-on directly from the AUR with pacman but the error persisted so I downloaded the source and compiled it.
Local package search shows that keepassxc Version : 2.4.2-1 is installed.
What is the problem here?
Is this a bug and will add-on work and still remain secure?
Will happily update to 5 stars if this can be rectified.
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reply to developer:
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Yeah, 2.4.3 was the source I downloaded and compiled through your link so I'm unsure as to why I only have 2.4.2-1.
I'll remove 2.4.2-1 completely and just install directly from source.
I'd rather rather not set 'check updates' to never so I'll leave that.
I was just concerned about possible incompatibility and security issues.
Thanks for quick response.
Will upgrade to 5 stars.

EDIT: Perfect now!

Great add-on, but I have to take a couple stars off because it doesn't have a dark theme for the drop down menu and settings page, which makes many sections illegible when using a dark theme in browser. Also the notification popup for saving new/updating entry either doesn't work or it's designed as only a flashing icon. Either way it'd be nice to see a popup like the default firefox popup for saving logins in-browser.

Using it on Linux and Windows, works great on both. Definitely makes using KeepassXC for all your passwords a little more convenient.

Just an nice password manager but the thing is sometimes the green key(for generating passwords) is all over the page

On Ubuntu with stock Firefox 67.0.1, KeePassXC-Browser 1.4.6, and KeePassXC 2.4.1 I'm getting the message "You use an old version of KeePassXC.
Please download the latest version from keepassxc.org.". It does appear 2.4.2 has been released, but wasn't able to install it using neither the PPA repo nor the snap package. Would an upgrade even resolve this?

I cannot add a database. The "Connect" button does nothing.

Won't connect to my database. The connect button does nothing. The reload button gives: Key exchange was not successful. KeePassXC 2.4.2 Firefox 67.0(64bit) on Mac OS X Mojave.

Дополнение работает хорошо, проблем не возникает.

Maybe adding the function of connecting with password-generator will make it perfect.

Somehow, Firefox deactivated the plugin today out of nowhere, needed to reinstall Firefox completely. Still, one of the best-working password-vaults I've used so far. Would be great, to be able to choose name/pw/submit fields with the html, not just with this field.

Nice. Works on FreeBSD too.

Version 1.4.2 makes this extension great again. It lets you use KeepassXC comfortably from within your favorite browser.

"Worked well till today. Now I get jQuery-Errors (Error: Permission denied to access "apply") at my WorpdPress-instance. Errors stop the moment I deactivete this plugin.
ATM everything else I worked with today runs fine.

Also the plugin worked fine for the last few months, so I would like to keep using it and will do so, trying to live with the deactivation hassle..."

Issue got fixed very quickly. Adjusted review to five stars.