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    • New note by bobjonkman 29 November 2020
      Bread machines are great. I haven't bought a loaf of bread in about three years. If #sonTwo's bread machine has custom settings, I recommend 20 min knead time, changing the rise times (1hr, 1.5hrs, 1.5hrs) and at least 60-70 min bake time. A good recipe is 1 cup water, 2.5 cups all-purpose flour, 2 tbsp […]
    • bobjonkman repeated a notice by lnxw48a1 29 November 2020
      RT @lnxw48a1 #sonTwo texted to tell me that his in-laws bought them a bread machine. Me: Oh, cool! I was thinking the same thing, but it's beyond my current budget. They can sometimes be competitive, but I'm more of *good, you're helping take care of our kids and grandkids*
    • New note by bobjonkman 28 November 2020
      I'm near the Great Lakes (about an hour's drive from either Lake Ontario or Lake Huron, depending whether I go South or West). It was 5C for most of the day, about 40F for your USians. Apparently that's normal for this time of year...
    • bobjonkman repeated a notice by lnxw48a1 28 November 2020
      RT @lnxw48a1 About halfway through today's #YoCo ( #yogurt and #coffee ). Indoor temperature is 60°F, outdoor temperature is 30°F. Outdoor cats' water dish has about 0.5in / 1cm of ice on top. Very glad I'm not near the Great Lakes right now.
    • Favorite 24 November 2020
      bobjonkman favorited something by lnxw48a1: @vegos I agree. To most organizations, their primary concern is reach. So they congregate on big #corpocentric #socnets, even when the central corporation running things is actively hostile to their point of view. Then they're butthurt when their accounts are shadowbanned. Years ago, I tried to persuade some local Black […]
    • bobjonkman repeated a notice by lnxw48a1 24 November 2020
      RT @lnxw48a1 @vegos I agree. To most organizations, their primary concern is reach. So they congregate on big #corpocentric #socnets, even when the central corporation running things is actively hostile to their point of view. Then they're butthurt when their accounts are shadowbanned. Years ago, I tried to persuade some local Black churches and ethic-focused […]
    • bobjonkman repeated a notice by lnxw48a1 24 November 2020
      RT @lnxw48a1 [techcrunch com] #Australia spy agencies caught collecting #COVID-19 app data #surveillance Source:
    • New note by bobjonkman 3 October 2020
      There's also Megablocks, the precursor to Duplo. And there are also Micro Megablocks, the same size as LEGO. The kits for Micro Megablocks were much better than the LEGO kits, making slightly larger models but using only standard bricks. The LEGO models were smaller, depending on many custom pieces specific to the kit, which were […]
    • Favorite 3 October 2020
      bobjonkman favorited something by clacke: Not only are Duplo blocks *like* Lego blocks, they *are* Lego blocks, and I don't just mean that Duplo is a Lego brand and produced in the same factory, the two systems are actually compatible.A Lego 2x2 block fits and sticks to the underside of a Duplo block, and the […]
    • bobjonkman repeated a notice by clacke 3 October 2020
      RT @clacke Not only are Duplo blocks *like* Lego blocks, they *are* Lego blocks, and I don't just mean that Duplo is a Lego brand and produced in the same factory, the two systems are actually compatible. A Lego 2x2 block fits and sticks to the underside of a Duplo block, and the nob on […]

Preparing for the Keysigning Cryptoparty, 2 Dec 2013

Posted by Bob Jonkman on 24th November 2013

Key Pair

Cryptoparty like it’s 31 December 1983!

At the next KWLUG meeting on Monday, 2 December 2013 I’ll be demonstrating how to do e-mail encryption with Thunderbird and Enigmail. If you’ve never used e-mail encryption before then bring a laptop, and we’ll create keys and learn how to use them. We’ll save the lesson with pointy sticks for another day.

For those people who already have GnuPG/PGP keys I’m also hosting a Formal Keysigning. Participants will introduce themselves, read their GnuPG key fingerprint, then anyone else is invited to vouch for that person:

Bob: “I’m Bob Jonkman, and my GnuPG fingerprint is 04F7 742B 8F54 C40A E115 26C2 B912 89B0 D2CC E5EA”

Andrew: “I’ve known Bob since the early days, and that’s really him”

This is a great way to expand your Web Of Trust to include people whose keys you might not otherwise sign (because you don’t know them very well, or they only have ID issued by an authority you don’t like). With all these introductions and vouchings the chance of someone misrepresenting their identity is vanishingly small, so you can trust that the key fingerprint they read is really associated with that person.

To make this process go smoothly I’d like to have a printout of all the participants’ keyIDs, UserIDs, and key fingerprints, which I’ll distribute at the keysigning. That way you can just check off each name/keyID/fingerprint as people read them, and then sign their keys later at your leisure. But to get that printout I’ll need the public key of anyone who would like to participate in the keysigning.

If you’re using Thunderbird and Enigmail then open the Key Management window, right-click on your key and select “Send Public Keys by E-mail”, and send it to me ( )

If you’re a command-line weenie then use

gpg --export 0xYOURKEYID > 0xYOURKEYID-public-key-for-YOURNAME.pgp

and send that file 0xYOURKEYID-public-key-for-YOURNAME.pgp to me (substitute your actual keyID and actual name as needed).

Of course, I’d prefer signed, encrypted e-mail, but public keys are public (so encryption isn’t necessary), and public keys should already be self-signed anyway.

Unfortunately, if you’re creating your keys for the first time at the meeting you won’t be able to send me anything now. You can still participate in the vouching process, and we’ll have an informal keysigning after the formal keysigning, where all you need to do is read your fingerprint straight from your computer and those people who already know you can sign your key.

I’m still working on the procedures for the formal keysigning; you can see the work in progress (and contribute!) on the Formal Keysigning page on the Wiki.

Thanx, and hope to see you on Monday, 2 December 2013!

–Bob, who is the Keymaster. Who will be the Gatekeeper?

The Cryptoparty keypair logo from the Cryptoparty Artwork repository on GitHub is available in the CC0Public Domain.

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Posted in Crypto, email, KWLUG, PGP/GPG, privacy | Comments Off on Preparing for the Keysigning Cryptoparty, 2 Dec 2013

Cryptography and Security Events in Kitchener-Waterloo

Posted by Bob Jonkman on 9th October 2013

The months of October and November are shaping up to have some great lectures and presentations on cryptography, security and privacy.

Sheet of paper, strips of paper

Keysigning materials

Yesterday started off with an informal keysigning at the KWLUG meeting. The presentation was on the Scratch programming environment, nothing to do with GnuPG/PGP or cryptography. But a few of us exchanged little slips of paper with our key fingerprints, verified that the name with the fingerprint matched the person we knew, signed the keys, and so improved our standing in the Web of Trust. I hope that this becomes a regular part of all KWLUG meetings. The more people that participate, the more confident we can be about the validity of keys we may not have verified ourselves.

Today I attended the first UofW CSClub lecture on Security and Privacy by Sarah Harvey. If you’ve been following the news about the Snowden revelations you’ll know why security and privacy is important. The room was full of computer science, math and cryptography students, so the discussions were deep and technical.

Sarah Harvey shows a slide of Edward Snowden

Sarah Harvey shows a slide of Edward Snowden

There was a vacancy in the November KWLUG meeting so I asked Sarah if she would repeat her lecture. Let’s see what the KWLUG bosses have to say

There are more CSClub lectures scheduled, check the schedule on the CSClub site.

M-209 cipher machine

KWCrypto logo, the M-209 cipher machine

I’ve volunteered to do a presentation on Encrypting E-mail with GnuPG, Thunderbird and Enigmail, followed by a formal keysigning. I’m developing the presentation notes and keysigning procedure on the KWCrypto Interest Group Wiki that was set up after the Kwartzlab keysigning party last year. Please join me on the Wiki and the mailing list — I’d appreciate the help.


Keysigning Materials picture taken by Bob Jonkman and released under a CC BYCreative Commons — Attribution — CC BY license.

M-209 cipher machine by Greg Goebel used under CC BY-SACreative Commons – Attribution-ShareAlike 2.0 Generic – CC BY-SA 2.0

Picture of Sarah Harvey taken by Laurel L. Russwurm and used under a CC BYCreative Commons — Attribution — CC BY license.

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Posted in Crypto, KWLUG, PGP/GPG, privacy, security | Comments Off on Cryptography and Security Events in Kitchener-Waterloo

Why I’m an E-mail Luddite

Posted by Bob Jonkman on 2nd October 2013

Statue of a Luddite

Luddite Memorial, Liversedge

The pervasive expectation of HTML everywhere came to light in a recent e-mail exchange:

Him: Bob, have a look at this video: LOLcats at work

Me: Did you intend to send a link with that?

Him: Yes, here it is: LOLcats at work

Me: Sorry, still no link. Remember, I don’t receive HTML e-mail…

Him: Wut? I’ve never heard of someone not receiving HTML e-mail!

E-mail was never designed for HTML; it is intended to be a plain-text medium. HTML is merely cobbled on, and mail clients have no standard way to render HTML messages, resulting in different displays on different mail programs. Some mail programs, especially those run from the command line, can’t show HTML rendered messages at all.

Although I use a graphical mail client (Thunderbird), I choose to not display HTML for two reasons:

1) Security: HTML mail can have Javascript code or other objects embedded. That’s a great way to get virus infections on your computer. I don’t want any code running on my computer that I didn’t put there myself.

2) Privacy: HTML mail that links to external images allows the owner of those images to track your mail usage: When you open the mail, how often you open it, the location you open it at, what computer you’re using, and whether you forward it to others (and then, when they open the mail, how often, their location, &c).

Not to mention that HTML messages are far bigger than text messages, especially when the HTML contains embedded images, fonts, and other stuff. Now, that’s not such a big deal with fast connections, unlimited download caps, and cheap disk drives, but it will still make a difference on small-format devices like phones and watches.

That said, if you do send me HTML e-mail, be sure to embed any images or LOLcat videos. That way I can still view them as static attachments, without revealing when, where, and how often I view them.

For more info have a look at the Wikipedia article on HTML e-mail


You can send HTML e-mail to Bob Jonkman at

The Luddite Memorial, Liversedge by Tim Green is used under a CC-BYCreative Commons — Attribution 2.0 Generic — CC BY 2.0 license.

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Posted in email, privacy, security | 1 Comment »

OpenDataDay Hackathon at Kwartzlab

Posted by Bob Jonkman on 27th February 2013

Open Data Waterloo Region


On International OpenDataDay four teams of hackers from OpenDataWR gathered at Kwartzlab to work on Food Premise Inspection Data, modelling new transit routes and route changes with GTFS data, improving the server for the Catchr transit app, a proof-of-concept pushbutton app for Android, and creating a Get Map button for OpenStreetMap in the Thunderbird Lightning add-in.

Hackers at Kwartzlab OpenDataDay Hackathon at Kwartzlab. Clockwise: Koo (back to camera), Ralph, Michael, Mike, Brett, Jonathan. Missing: Darcy, William, Katherine, Bob.


William and I worked on the Get Map button. Although we had hoped to create some working code, we got only as far as making a mock-up of Lightning’s Edit Event screen:

Screenshot of Thunderbird Lightning Edit Event screen
Lightning “Edit Event” screen, showing the new “Get Map” button


The first hurdle we ran into is that Lightning source code is kept in a Mercurial repository. Although William was familiar with Perforce (another code revision system), I haven’t used Mercurial until now. And the repository contained all of Thunderbird, Firefox, SeaMonkey, and the Mozilla addins. We certainly didn’t want to clone the entire Mozilla code base! So William found the Lightning tarball, which I unpacked in a new folder. This let us poke around the source files to find where our new code should go.

Then we found that Lightning isn’t straight Javascript, it’s mostly XUL. XUL is close enough to XHTML, CSS and DTD files that we could figure out what needed to be done. But we had a limited amount of time, and I didn’t want to spend it waiting for source code to build. So I created a new profile in Thunderbird, installed a fresh copy of the Lightning add-in, and we hacked at the installed files directly. This gave us instant feedback on the changes we made, just by restarting Thunderbird and running Lightning. Some of the changes were in plain text files, but others needed to be made to files in JAR format. One of those was the localized language file. We weren’t sure which language file we were using, en-GB or en-US. Of course, we picked the wrong one to start with, and spend maybe two hours trying to debug a misleading error message about a missing entity definition while we were working on the wrong file.

But it all turned out OK in the end. Now we need to take the work we did on the installed files and replicate it on the source files from the Mercurial repository, properly build Lightning from source, and offer our changes to the Mozilla Calendar project. And, once we’ve got it working, we’ll make the changes available on this site too.

–Bob and William.

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Posted in code, FLOSS, Open Data, Software | Comments Off on OpenDataDay Hackathon at Kwartzlab

Calendaring Server Software

Posted by Bob Jonkman on 12th October 2012

I’m looking for a free/libre calendar server to run on a GNU/Linux server.

It needs to have CalDAV connectivity, so that I can use Evolution, Sunbird or Thunderbird/Lightning as my only client. Ideally, it will also have a Web interface for both administration and calendar viewing, exports to iCal (.ics) files, supports iMIP, and offers Atom/RSS feeds of calendar items.

Here’s what I’ve found so far. If you know of others, please leave a comment.

There’s also a list at CalConnect’s CalDAV Servers

Name WebUI Export iCal (.ics) CalDAV
Admin View Edit iCal (.ics) iMip Atom/RSS
phpGroupWare       No     No
Chandler Project              
Zimbra Yes, but.. Yes Yes Yes   No Outlook only
EGroupware Community Version              
WebCalendar             No
Darwin Calendar Server              
Tryton Calendar              
ownCloud Yes Yes, but not Public, Read-only Yes No No No Yes
Citadel ? ? ? ? ? ? ?
Baikal ? ? ? ? ? ? ?
Horde ? Yes Yes Yes ? Maybe Yes

WordPress Plugins

The other calendars I’ve been trying are WordPress plugins. There is much promise in their description blurbs, but so far I’ve rejected most:

Name Export iCal (.ics) CalDAV Notes
iCal (.ics) iMip Atom/RSS
Calendar JCM         Rejected: no longer supported
Event Calendar / Scheduler         Rejected: missing .php modules when running
The Events Calendar         Rejected
WP Events Calendar Yes, with iCal for Events Calendar plugin   No No Works
My Calendar Only lists current month   Partial  
CalPress Pro ? ? ? ? This is a commercial plugin;
All-in-One Event Calendar by Timely By tweaking the “Add to Google” URL ? ? WebCal Possible privacy concern
  • 11 January 2011
    Originally posted
  • 26 March 2011
    Added Linuxaria’s suggestions
  • 16 April 2011
    Added WordPress plugin info; added CalDAV column; filled in some attributes
  • 11 October 2012
    Updated feature list for Zimbra
    I’ll be writing a review of Zimbra Open Source Edition soon, detailing some of my experiences (eg. requires Flash for the administrative Web interface)
  • 12 October 2012: Put WordPress calendars in table format, added My Calendar
  • 5 November 2012: Added Dosch’s suggestions
  • 16 November 2012: @Encyclomundist dents about
  • 26 September 2013: I’ve started to use ownCloud 5.0 as a calendar repository accessed with Lightning using WebCal. ownCloud doesn’t publish an iCal feed or have a public read-only view, but since it’s Free Software constantly under improvement I’ll stick with it for a while.
  • 9 November 2013: I think @postblue turned me on to Baikal: Using #Baikal to sync tasks, contacts and calendars
  • 9 November 2013: I’m now using Timely All-In-One on some blogs, will be upgrading others. It’s not the perfect iCal plugin, but the best one yet.
  • 9 November 2013: @McScx and @lxw37 both introduce me to Horde.
  • 13 August 2015: Just discovered Blaise Alleyne’s post on Degooglifying (Part IV): Calendar. This is pretty much the same solution I’ve settled on; ownCloud + Thunderbird and Lightning. I’m not quite as advanced as Blaise on the mobile front, though.

This is a “living” post, so it will float back to the top of the blog as I update it.


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Posted in Calendars and Schedules | 11 Comments »

How To Use OpenStreetMap with Thunderbird’s “Get Map” button

Posted by Bob Jonkman on 9th October 2012

Thunderbird’s address book has a “Get Map” button to show an address location on a map. By default, Thunderbird uses Google Maps to display a location. Wouldn’t it be nice to use OpenStreetMap in Thunderbird instead? Here’s how!



OpenStreetMap uses Nominatim to search for and display a location. The Wiki tells us the URL query is processed left-to-right, and the example shows the address elements from greatest to least resolution:,+birmingham&format=xml&polygon=1&addressdetails=1



The Thunderbird Knowledgebase for Mail and News settings gives us the following address-related parameters:

Substitution variables:
@A1: address, part 1
@A2: address, part 2
@CI: city
@ST: state
@ZI: zip code
@CO: country

Now we combine the two in Thunderbird’s configuration file prefs.js:

user_pref("mail.addr_book.mapit_url.format", ",@A2,@CI,@ST,@CO");

If you prefer not to edit the pref.js file, here’s a step-by-step procedure to do it with the graphical interface.

If you’re using Linux, select Edit, Preferences from the Thunderbird menu. On Thunderbird for Windows select Tools, Options. Click on the Advanced toolbar button, then the General tab.

Screenshot of the Preferences window, Advanced tab

Click on the Config Editor… button.

Screenshot of advanced configuration warning

Click on the I’ll be careful, I promise! button.

Screenshot of Thunderbird advanced configuration window

Type mapit in the Search field,

Screenshot showing the mail.addr_book.mapit_url.format setting

Double-click on the line for the mail.addr_book.mapit_url.format parameter.

Screenshot of input dialogue

Delete what’s there, and type,@A2,@CI,@ST,@CO

Screenshot of input box with OSM value

Click OK, close the about:config window, and close the Preferences window.

Now we need to find an address book entry with enough data to generate a map.

From the Thunderbird menu, select Tools, Address Book, and double-click on an entry. Click New Contact if there’s nobody in your address book (and you can enter your own address).

Screenshot showing address book general info entry form

Click on the Private or Work tab to show the screen for address entry.

Screenshot showing address book work info entry form

At minimum, fill in the Country field. Adding State/Province, City and Address will improve the resolution of the map. If you do fill in higher resolution fields (Address or City) then you also need to fill in the lower-resolution fields (State/Province and Country), or the Nominatim search won’t work.

Note that the Nominatim URL query doesn’t include the @ZI variable, so the ZIP/Postal Code field isn’t used to create the map.

When all the data is entered, click OK.

Screenshot of Thunderbird Address Book showing Bob Jonkman

With any address field filled in, the address book entry now displays a Get Map button.

Go ahead, click it!

Screenshot of OpenStreetMap

And there we have it! An OpenStreetMap of the address in the Thunderbird address book.

If you’ve done this, or have suggestions for improving these instructions please let me know in the comments or by e-mail at


All screenshots taken by Bob Jonkman, and freely available for re-use (CC0CC0).

The new OpenStreetMap logo by Ken Vermette from, used under a Creative Commons LicenseCC BY-SA license.

The Thunderbird Logo and Wordmark are used according to the Mozilla Foundation Visual Identity Guidelines for Thunderbird.

Maps © OpenStreetMap contributors, CC BY-SA

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Posted in FLOSS, Google Free, How To | Comments Off on How To Use OpenStreetMap with Thunderbird’s “Get Map” button

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