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Firefox asking to be made the default browser again and again

Linux

Firefox on Linux can develop the habit to (rather randomly) ask again and again to be made the default browser. E.g. when started from Thunderbird by clicking a link it asks but when starting from a shell all is fine.

The reason to this is often two (or more) .desktop entries competing with each other.

So, walkthrough: (GOTO 10 in case you are sure to have all the basics right)

update-alternatives --display x-www-browser
update-alternatives --display gnome-www-browser

should both show firefox for you. If not

update-alternatives --config <entry>

the entry to fix the preference on /usr/bin/firefox.

Check (where available)

exo-preferred-applications

that the "Internet Browser" is "Firefox".

Check (where available)

xfce4-mime-settings

that anything containing "html" points to Firefox (or is left at a non-user set default).

Check (where available)

xdg-settings get default-web-browser

that you get firefox.desktop. If not run

xdg-settings check default-web-browser firefox.desktop

If you are running Gnome, check

xdg-settings get default-url-scheme-handler http

and the same for https.

LABEL 10:

Run

sensible-editor ~/.config/mimeapps.list

and remove all entries that contain something like userapp-Firefox-<random>.desktop.

Run

find ~/.local/share/applications -iname "userapp-firefox*.desktop"

and delete these files or move them away.

Done.

Once you have it working again consider disabling the option for Firefox to check whether it is the default browser. Because it will otherwise create those pesky userapp-Firefox-<random>.desktop files again.

Configuring Linux is easy, innit?

Thunderbird startup hang (hint: Add-Ons)

Debian

If you see Thunderbird hanging during startup for a minute and then continuing to load fine, you are probably running into an issue similar to what I saw when Debian migrated Icedove back to the "official" Mozilla Thunderbird branding and changed ~/.icedove to ~/.thunderbird in the process (one symlinked to the other).

Looking at the console log (=start Thunderbird from a terminal so you see its messages), I got:

console.log: foxclocks.bootstrap._loadIntoWindow(): got xul-overlay-merged - waiting for overlay-loaded
[.. one minute delay ..]
console.log: foxclocks.bootstrap._windowListener(): got window load chrome://global/content/commonDialog.xul

Stracing confirms it hangs because Thunderbird loops waiting for a FUTEX until that apparently gets kicked by a XUL core timeout.
(Thanks for defensive programming folks!)

So in my case uninstalling the Add-On Foxclocks easily solved the problem.

I assume other Thunderbird Add-Ons may cause the same issue, hence the more generic description above.

Dovecot segfaulting (Ubuntu 14.04 LTS, CentOS 6 and 7)

Open Source

We're currently installing a solution including dovecot for a company to go into production in April. So we kick this off with a development box for integrating parts that different suppliers to our customer are working on.

But after installing dovecot on the new joint development machine it just didn't start. It worked on our local development boxes but the install for the customer has been scripted with (what we call) "poor man's puppet" so it is somewhat hard to compare the setups. Same Ubuntu 14.04 LTS under the hood but on top of that things (like config layout, directory structures etc.) are quite different.

Back on topic: ps aux | grep d[o]ve returned empty.

Looking at /var/log/mail.log did not show anything relevant.

But syslog (/var/log/syslog) had some worrying lines like:

Mar 16 03:16:17 dev-new kernel: [ 3222.339365] doveconf[6420]: segfault at 200 ip 00007fa041b25a03 sp 00007ffe7881e070 error 4 in libc-2.19.so[7fa041ada000+1bb000]

Manually running the daemon resulted in:

# /usr/sbin/dovecot -F -c /etc/dovecot/dovecot.conf
Segmentation fault

So

mkdir /var/core
chmod 1777 /var/core
echo "/var/core/%p" > /proc/sys/kernel/core_pattern
ulimit -c unlimited
/usr/sbin/dovecot -F -c /etc/dovecot/dovecot.conf
Segmentation fault (core dumped)

Better. We have a core file now.

But:

Continue reading "Dovecot segfaulting (Ubuntu 14.04 LTS, CentOS 6 and 7)"

iTunes starts but does not show the main application window

IT

Every once in a while iTunes on Windows decides to start but does not show the main application window when trying to sync an iPhone (or any other iDevice).
May be it pops up after half an hour, may be not.

This behavior is caused by iTunes waiting for its Bonjour zeroconf network service. Unfortunately though iTunes is updated very frequently that bug is persistent for years now.
The work-around is easy though:

Open up CMD as Administrator and type

net stop "bonjour service"

and iTunes should pop up its window a few moments later. It will complain about Bonjour not running but that is not needed for anything but network self-discovery. Which you usually don't need anyways.

If you do, you can start Bonjour again with

net start "bonjour service"

anytime also while iTunes is running. Once it decides to show its main window, it's fine to go for the session.

Screenshot of iTunes and the CMD window

Firefox opens directories in RawTherapee ... or a tale of colliding assumptions

Internet

After installing RawTherapee, a raw photo to jpg image converter, on my Kubuntu 13.04 desktop, Mozilla Firefox started to open the Downloads directory in ... RawTherapee. Gosh. Now that's what you'd want to browse a downloads folder with.

Update-alternatives did not help as RawTherapee is not managed by the Debian alternatives system. Hm, xdg-open still works as intended and opens dolphin.

Asking Google turns up many not working solution proposals. Hm.

Firefox: Context menu (right click) -> Open Containing Folder

But, searching the collective memory is not completely useless. There is a solved bug report on the RawTherapee bug tracker that explains the issue. The .desktop file RawTherapee installs contains inode/directory as a supported mime type. Well, that's technically correct but makes no sense in the way mime associations are used. Thankfully the bug reporter was able to convince the developer of this and get this fixed for future RawTherapee releases.

So option 1: edit /usr/share/applications/rawtherapee.desktop and remove the inode/directory entry from the MimeType=-line. Then regenerate the various mimetype caches.

This still bears the question why Firefox does not use the inode/directory entry from dolphin.desktop. Also, the next update from Debian/Ubuntu will probably overwrite the fixed rawtherapee.desktop file again as the patch from the Rawtherapee developer will only be included on new releases (and these may or may not be backported to Debian/Ubuntu). So you'd need to copy that fixed rawtherapee.desktop file to ~/.local/share/applications/ or the like.

Option 2: find out what the real issue is...

Continue reading "Firefox opens directories in RawTherapee ... or a tale of colliding assumptions"

Fix Umlauts in the XFCE Terminal

IT

The XFCE Terminal has the weird issue of sometimes showing question marks (?) instead of German Umlauts (äöüÄÖÜ) although they work fine in any other stock XFCE application (e.g. the default editor "mousepad").

The solution to this can be found on the XFCE Forums but it took me quite some time to find it. It was difficult to find a suitable search query to dig out that page. Google turns up a lot of irrelevant stuff on "XFCE Terminal question marks"...

XFCE Editor Umlauts with and without LANG variable set

The problem with Umlauts (and other 8bit ASCII characters) showing as question marks arises if the user has no LANG variable set.

A simple

export LANG=en_US

resolves the issue. Put that into ~/.bashrc or any other place suitable in your distribution.

Gentoo users may want to

su  # become root
echo "LANG=en_US" >> /etc/env.d/02locale
env-update
exit
source /etc/profile

to set the LANG variable system-wide.

So keywords, dear Google: Umlaute, deutsch, Fragezeichen, kaputt, falsch, broken, display, zeigt, charset, Zeichensatz :-)

Seredipity default event_s9ymarkup plugin breaking URLs that contain underscores

Serendipity

The default Serendipity mark-up plugin (event_s9ymarkup) currently breaks URLs that contain underscores.

So

http://en.wikipedia.org/wiki/Statler_%26_Waldorf

will end up

http://en.wikipedia.org/wiki/Statler</u>%26_Waldorf

because of a faulty regex. Garvin Hicking does not really want to fix this. (See this s9y support forum article for arguments pro/contra fixing it). So if you encounter this problem, your options are:

  • replace _ in URLs with %5F (aka manually urlencode it)
  • remove the plugin or disable it
  • patch the plugin

Patching is basically changing

plugins/serendipity_event_s9ymarkup/serendipity_event_s9ymarkup.php:

$text = preg_replace('/\b_([\S ]+?)_\b/','<u>\1</u>',$text);

to

$text = preg_replace('/\ _([\S ]+?)_\ /',' <u>\1</u> ',$text);

If you want to be writing things like "Haha[lol]" (which I have no real use for ...), extend the "\ " with whatever you'd like to be o.k. to delimit bolded words beyond blanks. It should only be symbols that are not valid in URLs (so none of "$-_.+!*'()," which are all valid in URLs according to RFC 1738).

You may also want to consider replacing one underscore ("_") with two or more ("__") to make the detection, that you actually wanted to write bold text, more reliable.

SSHd chroot and PAM

Gentoo

SSH with chroot patch has been working fine for a number of years. Since PAM v0.99 things have broken though, if users are chrooted with the "/home/username/./" syntax as their homedir.

SSH sessions will just terminate immediately after successful logon. Doh.

Two solutions exist:

  1. Put UsePAM no into /etc/ssh/sshd_config and use the chroot patch and /./ in users homedirs
  2. Keep UsePAM yes. Emerge sys-auth/pam_chroot and add session required pam_chroot.so to /etc/pamd.d/sshd setup /etc/security/chroot.conf or add a chroot_dir=/home/username/ to the pam_chroot.so line.
    This will currently not work for amd64 though as the Gentoo bug regarding pam_chroot has not cought any attention from the arch testers. Since July...

Bugging the arch testers in #Gentoo-amd64 didn't help either:

Continue reading "SSHd chroot and PAM"

Apache fails to start at boot, but works when started manually

ApacheGentoo

Since a baselayout update Apache fails to start on Gentoo at (re-)boot of a server if that server has unused ethernet interfaces.

The symptom is that Apache fails to start on boot although it has been added to the runlevel with
rc-update add apache default

This is caused by recent baselayouts not working properly with more than one eth and not all of them being up.

Thus changing depend() { need net ... } into
depend() { need net.eth0 ... } at the top of /etc/init.d/apache2 will help.

While you're at it you could also add an nice after urandom to the existing depend () construct
and make sure apr and apache are emerged with flag urandom set. Reading from /dev/random to initialize the digest authentication mechanism (or SSL for that matter) might cause apache to block otherwise if there is not enough entropy in the random pool.