If like me you have a full-time job and a mandatory Windows PC dedicated to you at your office (stuffed with proprietary software), it may be a challenge to keep your privacy while syncing your mail, contacts and calendars.
Although Roundcube works perfectly to manage mails, the Debian repo did not include a Cardav extesion to access your Radicale contacts. To overcome the issue, I managed to install a third party extension that you can follow here. Additionally, I also found a sieve extension that you can use to have Roundcube filter, forward emails and even send “out-of office” responses. Have a look here to install the sieve extension. To further boost the use of the webmail client, I also applied a small tweak to PHP for increasing message attachment size limit to 75M. Have a look here on how to do this.
All-in-all, Roundcube was perfectly satisfying to use my FBX server send/recieve mails and manage all my contacts from a web-browser. What was missing though was a proper Caldav web-client to manage and sync my calendars.
I have a full time job but also try to manage side-hustles from time to time. Managing my time for both along with keeping up with the family agenda (i.e. pick up kid from school take to doctor etc.) and tracking my personal chores, I desperately needed all calendars on the same page.
Now at work, my offices uses gmail. There was no way I wanted to share my personal credentials or my calendars with that group, so that option was out instantly. My other option was to use a mail app in windows (i.e. outlook) but, that worried me just as much. Additionally, in any case I quit my job or was let go, I may not have a chance to remove my accounts from the computer they gave me. So, that led me further to search for a web-client that I could run on my FBX and access without too much worries.
Unfortunately, there are no viable FOSS alternatives out there. AgenDav was not for me; anyone with the address to my calendar could see it (out goes privacy - I also had some problems installing but that was me), there seems to be an extension for Roundcube but my technical knowledge was not enough to get it running, Infcloud exists but hasnt been maintained for many years (and it’s UI is “really” outdated - dont want to look at that :), Bloben was developed but hasnt been maintained for over a year (and it seems docker only)… So, I really couldn’t find an option.
In the end, Syncthing came to my rescue. It makes you wonder doesn’t it : ) Well, what I did was have Syncthing run on my Windows user account and created a single folder that syncs with my phone (and FBX). In this folder, I installed a portable version of Thunderbird and configured it to work with my mail, address books and calendars (along with my work calendar). It did the job as my client, was FOSS and gave me the chance to remotely remove it when / if necessary.
The reason I’m posting this is, there may be others in my position and maybe this post will save some of their time for a practical solution to such a need. If you have any other tips you would like to share, please feel free to add as you see fit.
Thanks and good luck.