Tony Mechelynck

About me

Developer Information
Name Tony Mechelynck
Location Brussels, Belgium
Occupation retired
User since March 5, 2007
Number of add-ons developed 1 add-on
Average rating of developer's add-ons Rated 4 out of 5 stars

In a little more detail...

Homo sum, et humani nihil a me alienum puto.

Add-ons I've created

Nightly Tester Tools Compatible with Firefox 57+

Nightly Tester Tools (NTT) is an add-on for aiding testers of Nightly builds of Mozilla apps including Firefox.

Rated 4 out of 5 stars (193)
14,248 users

My Reviews

Addons Recent Updates

Stopped working today (between 6 and 7 March 2017) on SeaMonkey Rated 5 out of 5 stars

Sorry, I know that bug reports are not supposed to come here but I didn't find any better place. Let's hope the developer reads the users' reports.

First known bad:
UA:"Mozilla/5.0 (X11; Linux x86_64; rv:55.0) Gecko/20100101 Firefox/55.0 SeaMonkey/2.51a1"
ID:20170306145452 en-US

Last known good:
Same UA and localization (or lack thereof) as above, except that the "last good" build had Firefox 54.0a1 with SeaMonkey 2.51a1 which is more normal.

Using Addons Recent Updates 0.1.7 in both cases.

Symptom: Even though the extension's pref is set to 366 days, I only see a couple of days' worth of updates in about:addons

Best regards,

*Edit* After installing the development version from it works again (see details on the issues page mentioned in the developer's reply).

This review is for a previous version of the add-on (0.1.7). 

Html Validator beta works with trunk SeaMonkey on Linux64 Rated 5 out of 5 stars

I've been testing HTML Validator Beta with no problems on the version of SeaMonkey mentioned below, comparing "Tidy" results with "SGML" results. In particular the "Tidy" version found attribute errors (including quite a number of mismatches due to typos between the name= and id= attributes of <a> tags). :-)

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:50.0) Gecko/20100101 Firefox/50.0 SeaMonkey/2.47a1
Build identifier: 20160625075045

Great that it has ceased being "Windows-only".

P.S. One unclosed <a> tag caused several "anchor already defined" warnings, but once I had noticed and fixed the error the spurious messages disappeared.

This review is for a previous version of the add-on ( 

DOM Inspector

A must-have Rated 5 out of 5 stars

I have quite some user CSS (both userChrome and userContent) and this tool is a must-have to find out how to tweak the browser's look and feel (and also that of some IMHO less-than-ideally written web pages).


Rated 5 out of 5 stars

Subdued, economical of chrome real estate, and regularly maintained (the latter is getting rare these days): I love it. (And for whoever likes "flashy" rather than "subdued" there is also "LCARSTrek", by the same author.)

This review is for a previous version of the add-on (2.38). 

Domain Whois

Supports only Russia? Rated 1 out of 5 stars

Trying to see if this add-on would be worth installing, I go to its homepage, which is in Russian. It has what looks like a search box for domain names, with the title «Для получения информации введите имя домена или IP-адрес:» which IIUC means "To obtain information enter a domain name or IP address". So I try "" then "" then a few more (none of them in Russia), and the only answer I get (every time) is «Неверно введено имя домена!» which IIUC means "Invalid domain name entered!»

Keyword Search

Just the search I needed Rated 5 out of 5 stars

Thanks to this extension I don't need to change any settings to use the English Wikipedia when typing in the URL bar, the French Wikipedia in the Search bar and the aw<s>esome</s>ful bar, and DuckDuckGo on right-click.

I love it.

This review is for a previous version of the add-on (1.1.6).  This user has a previous review of this add-on.

Словарь синонимовъ RU

Word-ending hard sign: Pre-1917 orthography? Rated 3 out of 5 stars

Once upon a time, every single Russian word had to end with either a vowel, a soft sign (ь, мягкий знак) or a hard sign (ъ, твёрдый знак). This was a leftover from when the latter two were pronounced as very short instances of the vowels i and u respectively, and no consonant could end a word; but since in the meantime they had become diacritical signs telling the reader whether the preceding consonant was soft of hard (and word-ending consonants had reappeared by virtue of the muting or almost-muting of these extra-short vowels), it was decided (as part of the 1917 reform IIUC, when my late grandfather was a teenager) to remove the hard sign in that position. It only remains where a prefix ending in a hard consonant is followed by a yod, e.g. in the verb съесть (to eat, perfective, ← с + есть).

I wonder if this dictionary also uses other letters long disappeared from current orthography. For instance, does it spell "мѣждународный" with ѣ, as under the Czars? (In modern spelling, the synonym pair would be международный = интернациональный, "international".)

PDF Viewer(discontinued)

Doesn't always work Rated 3 out of 5 stars

Mozilla/5.0 (X11; Linux x86_64; rv:36.0) Gecko/20100101 Firefox/36.0 SeaMonkey/2.33a1 ID:20141110003001 c-c:8ab46a67ce9e m-c:d380166816dd

It doesn't always work, I don't know why; I suppose it's something in the PDF file which makes it never stop "loading" with a rotating throbber in the middle of a blank (or almost blank) page. But when I have this problem I can invoke the standalone Acrobat Reader on the same file by means of the "Download" button near top right (which has options "Save to disk" and "Open in acroread").

Remember Passwords

Rated 3 out of 5 stars

In SeaMonkey 2.29 (based on Toolkit v32) and later, this extension "hides" all saved passwords. Getting mail becomes impossible because the saved password is not seen and a new one is not asked for.
Downgrading makes the passwords reappear. Also disabling the extension which IIUC is unncessary in Toolkit v30 (SeaMonkey 2.27) and later.


Rated 5 out of 5 stars

Bugmail 2.0 from
After updating from SeaMonkey 2.27a1 to 2.31a1 the extension stops working (no more bugmail display when viewing a bugmail from I'll try Colin Guthrie's version.
Here are my UA strings, build IDs, and CSIDs:
2.27a1: Mozilla/5.0 (X11; Linux x86_64; rv:30.0) Gecko/20100101 Firefox/30.0 SeaMonkey/2.27a1 ID:20140214003001 c-c:1ce77c2f9bd0 m-c:d275eebfae04
2.31a1: Mozilla/5.0 (X11; Linux x86_64; rv:34.0) Gecko/20100101 Firefox/34.0 SeaMonkey/2.31a1 ID:20140723133406 c-c:acb745a4d796 m-c:d0f6259e8446

-- AMO gives contrary messages (about 1.6.1): "Works with SeaMonkey 2.0a1and later" and "Not available for SeaMonkey 2.31a1".
-- "Please do not post bug reports in reviews, see the support section"... of which there is none.

This was an excellent add-on… while it worked.

This user has 2 previous reviews of this add-on.


Wow! Rated 5 out of 5 stars

Even if it had been only a "styling-only" add-on, having such a nice page with the application logo (SeaMonkey, in my case) rather than Mozilla's bland XUL page would have been a huge bonus; but on the "Page not in cache" page I noticed a "Search" button which IIRC wasn't present in Mozilla's XUL. I didn't use it (I had a link to the desired page on another tab) but I'll have to find out exactly what it does.

P.S. And the application-specific add-on manager logo is a nice touch. Already too many of my SeaMonkey extensions have descriptions saying “for Firefox” or “for Thunderbird”.

This review is for a previous version of the add-on (1.3.20130808.1-signed.1-signed). 

Lightweight Themes Preview for SeaMonkey

When enabled, disables hovering over "Apply Theme" submenu Rated 1 out of 5 stars

Mozilla/5.0 (X11; Linux x86_64; rv:27.0) Gecko/20100101 Firefox/27.0 SeaMonkey/2.24a1 ID:20130919003001 c-c:1ea1fc3586db m-c:803189f35921

Lightweight Theme Preview for SeaMonkey 0.1

When this extension is enabled, moving the mouse from "Apply Theme ▶" in the View menu to the submenu thus opened, immediately closes both the View menu and the submenu.

If there is a support forum for this extension, I haven't found it, sorry.

Lightweight Themes Manager

Rated 5 out of 5 stars

When many lightweight themes are installed, this add-on makes managing them extremely easy, including (but probably not limited to):
-- telling lightweight themes and complete themes apart from each other (in the Add-on Manager they appear interspersed in a single list; this extension opens a page listing only lightweight themes);
-- checking how a lightweight theme other than the current one would look like if it were enabled (by hovering the mouse over the thumbnail);
-- finding which lightweight themes were installed from an obsolete URL (such as and need to be refreshed if they are to be used again in the future. (These "obsolete" add-ons are shown in the LWTM without a thumbnail.)
---- WARNING: Reinstalling the same lightweight theme, but from a working URL (such as, which can be done by means of the link in the LWTM page, won't make the obsolete entry disappear; and AFAICT there is no [_Uninstall_] button for lightweight themes. AFAIK the only way to uninstall a lightweight theme consists of removing the corresponding {...} entry, with one (but not both) of the separating commas around it, in the value of the preference lightweightThemes.usedThemes in about:config. Since that value can be extremely long, especially if many lightweight themes are installed, I recommend to do this as follows:

1. In about:config, find the preference lightweightThemes.usedThemes, right click it, and select "Copy Value";
2. Paste the value into your favourite text editor and edit it there;
3. Copy the new value (as it appears in your editor) to the clipboard;
4. in about:config, double-click lightweightThemes.usedThemes (the old value will appear, selected, in an input box in a popup) then click Ctrl+V (to paste the new value which you copied at step 3) then click the [_OK_] button at the bottom of the popup. If you then refresh about:addons or the LWTM (or both) you should notice that the unwanted entry has disappeared.

P.S. Of course, in Thunderbird, about:config is the "Config Editor" which can be opened by means of a button in the "Advanced" preferences.

This review is for a previous version of the add-on (0.1a10.1-signed.1-signed). 

Zippy Extension Packager

Where is this menuitem? Rated 4 out of 5 stars

Mozilla/5.0 (X11; Linux x86_64; rv:27.0) Gecko/20100101 Firefox/27.0 SeaMonkey/2.24a1 ID:20130919003001 c-c:1ea1fc3586db m-c:803189f35921

Zippy Extension Packager 17

The "Create XPI" menuitem is not to be found in the context menu for extensions in the "Recent Updates" tab of the Add-ons Manager. In the "Extensions" tab it is present, at the very bottom under a separator.

This review is for a previous version of the add-on (17.1-signed.1-signed). 

Keyword Search

Ah, great! Rated 5 out of 5 stars

It used to be that I could search with Wikipedia(en) in the URL bar and with either Wikipedia(fr) or the Mozillazine Knowledge Base in the Search bar but now (without this add-on) it seems that changing the one changes the other too.

I hope that it will work with SeaMonkey 2.23, currently «Mozilla/5.0 (X11; Linux x86_64; rv:26.0) Gecko/20100101 Firefox/26.0 SeaMonkey/2.23a1» ID:20130829003001 c-c:2e8458f26a91 m-c:aebdc69b02e5 even though when I try to install it AMO warns me that «I need Firefox 10.0 or higher» (then installs it if I okay the warning).

Edit: To make it work, you have to enter your search keyword(s) in the URL bar _and hit Enter_. Using the up-down arrows to select the search widget for the URL bar, or (of course) searching with the search bar, will get you your current search engine as set in the Search bar, in SeaMonkey's "Edit → Preferences → Browser → Internet Search", and in the about:config pref “”.

This review is for a previous version of the add-on ( 


Rated 5 out of 5 stars

Nice! (And reassuring: of 70 enabled extensions, the biggest ones are Adblock Plus, ChatZilla and "SeaMonkey", all the rest is below 3 MB apiece, total 135 MB).

This review is for a previous version of the add-on (6.1-signed.1-signed). 

QuickFolders (Tabbed Folders)

Great and well-maintained! Rated 5 out of 5 stars

Not only this is a great add-on to enhance the mail windows, its author is actively maintaining it for both Thunderbird and SeaMonkey, diligently reading bug reports and fixing problems found by users of both mailers on all three of Windows, Linux and Mac, and on 32- and 64-bit processors. :-) :-) :-)

This review is for a previous version of the add-on (3.10). 

Config Descriptions

Rated 5 out of 5 stars

A must-have for serious hackers who are not afraid of “voiding their warranty” by setting preferences yet still prefer to know what they are doing. :-)

Tabs Menu

For me this is a must Rated 5 out of 5 stars

This extension (which works even in SeaMonkey 2.8a1 if I override compatibility checking) allows me to jump easily and fast to any of my about 200 open tabs (at the moment), in conjunction with the following userChrome.css rules to remove the all-tabs button on the tab bar (where real estate is in high demand) and replace long menus' scrollbuttons by a scrollbar (so I can scroll them faster):

* hide all-tabs-button on tab bar in favour of Tabs Menu extension on menubar
* Gecko 2, 2010-12-29 and later
tabbrowser:not(#tabmail) .tabs-alltabs-button
{ display: none !important
* give the menus a scrollbar when they are too high to be
* displayed in full
menupopup scrollbox, #contentAreaContextMenu scrollbox
{ overflow-y: auto !important
* eliminate scroll buttons at top and bottom of the menus
menupopup autorepeatbutton, #contentAreaContextMenu autorepeatbutton
{ display: none !important

I love it.

Display mailing list header

Works with the latest nightlies Rated 5 out of 5 stars

This add-on works for me (with a compatibility override) even in SeaMonkey 2.6a1 without Mnenhy or Enigmail, even though it only advertises support for the long-gone SeaMonkey 1.0 and only with either of these other extensions enabled.