Tag: Obsolete Troubleshooting

Posted on
by

I tried out the Chrome beta for Linux on two different computers yesterday. On the first one, Flash worked right “out of the box.” On the second, it wouldn’t even show up in about:plugins. I couldn’t figure out what was different.

  • Both are 64-bit systems running Fedora 12.
  • Both are running the 32-bit version of Flash from Adobe’s yum repository.
  • Both are running the 64-bit version of Google Chrome from the beta download page.
  • I had run mozilla-plugin-config -i to create the 64-bit wrapper on both computers after updating Flash. (A security update came out yesterday.)
  • Flash works just fine in 64-bit Firefox and Opera.

I looked thoroughly at my home computer last night and came up empty. This morning I took another look at my work computer — the one where Flash actually showed up — and I think I’ve found it.

Chrome is using nswrapper_32_64.libflashplayer.so according to about:plugins. The actual file is in /usr/lib64/mozilla/plugins-wrapped/. This system has two symbolic links to that file, one in /usr/lib/mozilla/plugins/ and one in /usr/lib/mozilla/plugins-wrapped/. IIRC Only one of these was present on my home computer.

So I think this will fix it:

ln -s /usr/lib64/mozilla/plugins-wrapped/nswrapper_32_64.libflashplayer.so /usr/lib/mozilla/plugins/

Run the command as root or using sudo.

I’ll check back tonight and update this entry to show whether it worked.

Update: Yes, it worked!

Posted on
by

With the release of Firefox 3.5, I decided it was finally time to get serious about setting up a custom headline font on Speed Force. Cross-platform @font-face embedding in CSS is now possible on Firefox, Safari, the beta version of Opera, and (I think) Chrome. So I pulled out some bookmarks, looked for some fonts with licenses that allowed embedding, messed around with a test page and finally settled on two custom fonts: one for the post headlines, and one for the title and the sidebar section headers.

I tested it in a couple of browsers, both on my Linux desktop and on the Mac laptop, and planned to test it on the Windows desktop when Katie was done with it. But then something weird started happening.

Firefox started crashing. Repeatedly. Not quite predictably, but only when that test page was open.

I figured maybe it was a corrupted font, so I removed one, then the other, then both. If the page tried to download an embedded font, Firefox would eventually crash. If not, it was rock solid.

This seemed kind of bizarre for such a high-profile new feature to cause consistent crashing.

I did some searches online but didn’t come up with anything until I tried running Firefox from the command-line, so that I could read the error message. It complained, "firefox: cairo-ft-font.c:554: _cairo_ft_unscaled_font_lock_face: Assertion `!unscaled->from_face' failed." Searching for that led me to Fedora bug 509501 and bug 502274, and this blog entry.

To make a long story short:

  • On Linux, Firefox uses a library called cairo to handle graphics, including fonts.
  • An old version of cairo had a bug that would cause crashes with fonts under certain circumstances.
  • Cairo fixed the bug in December.
  • Fedora 11 is still using the old version of cairo.

So until Fedora ships a newer (or at least patched) version of cairo, my primary browser on my primary desktop will crash on any web page with an embedded font.

Nice.

I guess I could patch my own system for now and put the fonts up for the benefit of the rest of the Firefox+Safari+Opera-using audience on Windows and Macs (and probably other Linux distributions). But that means causing a crash for anyone else running Fedora 11 when they visit my site. I’m not too thrilled about that idea. I have no problem with adding enhancements that only appear under certain browser+os combinations, but actively crashing a browser? Not something I want to do.

Update (July 21): Aha! Fedora submitted an updated cairo for inclusion in the stable release last night!

Posted on
by

Well, Flash 10 is out with new features, security updates, and a fix for a Firefox video problem that I never noticed because it only affected Windows, and only sometimes.

It seems a little less stable than version 9 on Linux, at least 64-bit (it’s kind of complicated, because they only have a 32-bit program, so you either need to run a 32-bit version of your web browser, or use a wrapper that will let the 64-bit browser talk to the 32-bit plugin. nspluginwrapper does this for Firefox and other Gecko browsers, while Opera has a wrapper built in). But the annoying part: WordPress’ image upload no longer works.

Current versions of WordPress use SWFUpload to provide an enhanced file uploader. If you don’t have Flash installed, it will just use the standard upload dialog built into your web browser, but then you’re stuck uploading one image at a time — a real pain if you’re making a photo gallery post. Unfortunately for upload libraries, Adobe removed the ability for the Flash API to open a file dialog for security reasons.

So now, you can click on the button, but the dialog never opens. WordPress is tracking the issue in ticket 6979, which mentions that SWFUpload is discussing workarounds, and the YUI Uploader has already released a new version that works with Flash 10.

An update of some sort is likely to happen soon. In the mean time, WordPress users have two choices: hold off on updating Flash, or stick with the browser uploader for now.

Update October 31: SWFUpload has a new version in beta which works with Flash 10, and WordPress is working on integrating the update. It’s targeted for WordPress 2.7, which comes out in a little under two weeks, though the 2.7 writeup lists it as a feature that “didn’t make it” and might be in 2.8. (This seems like something that would affect enough people that I’d hope they would include it, even if it means pushing back the release a few days for more testing.)

There’s also been talk about implementing a file uploader using Gears, which I’d find really appealing if I weren’t 64-bit Linux both at home and at work.

Update November 1: I’ve tested WordPress 2.7 Beta 1 (not on this blog) and can confirm that the fix is included, as I was able to upload two images in one transaction.

Posted on
by

Experimenting with the new Automattic Stats Plugin that uses the WordPress.com statistics infrastructure to track traffic. So far, so good… except for one problem. Titles and links are missing from all the “most visited” posts. They’re just listed as numeric IDs.

Update: Actually, today’s posts seem OK. The plugin seems to just send the blog ID and post ID. I’ve been trying to figure out how the central server is retrieving the permalink and title. It doesn’t look like Bad Behavior is blocking it. And it doesn’t seem to be using the RSS feed, since posts that are still on the front page (and presumably still in the feed) are also showing up as numbers. *grumble*

Update 2: I just noticed that all of the number-only posts show the same placeholder graph showing “Region A” vs. “Region B” for 2003-2005.

Update 3: It’s a problem with WordPress’ XMLRPC interface, and affects other uses (like connecting with Flock). I’ve got a workaround, though (see comments).

Update 4 (May 10): Thanks to the pingback below from dot unplanned, it’s confirmed to be a bug in PHP 5.2.2. With any luck, the workaround will cease to be necessary when the next PHP bugfix is released.

Posted on
by

Upgraded to WordPress 2.0.6 and now feeds are broken. At least, they’re broken in Firefox, IE7, and KDE (Konqueror & Akregator). Something seems to be interrupting the transfer, causing them to get a blank file. Oddly, they work fine in Opera, the LWP “GET” command-line utility, and Dillo (not that Dillo can do anything but display the source, but it gets the whole file.) Even more oddly, SeaMonkey seems to have no problems. You’d think Firefox and SeaMonkey would have the same issues. Also, I seem to be able to sometimes get it to work on reload.

Anyway, I’m working on it. If you read this site via RSS or Atom, and it is working, let me know (and let me know which feed reader you’re using). I suppose it could be cookie-related, though I’ve already tried clearing cookies. I’ve also tried disabling just about every plugin I use that does something to feeds or headers, to no avail.

Update: I think I’ve got it. By using the Tamper Data extension, I was able to determine that the 304 Not Modified status was not being set properly. Instead of actually issuing the 304 status, it would issue a 200 OK, then send a Status: 304 header later in the response. It never showed any problems on command-line GET or HEAD because they weren’t conditional. That’s also why forcing reload would work.

I looked into wp-includes/functions.php and found the status_header function. Then I looked at the following line:

@header("Status: $header $text");

In theory this should work. Traditionally, setting a “Status” header will replace the actual HTTP status. But that’s not how the PHP manual says to do it. They suggest issuing the actual header that the server would send: HTTP/1.1 304 Not Modified. I noticed that the header function in PHP has some optional parameters, including one to force the HTTP status. That felt a little cleaner than hard-coding the protocol (since an older browser might make an HTTP/1.0 request, and it should get an HTTP/1.0 response), so I changed the line to this:

@header("Status: $header $text", TRUE, $header);

It seems to have fixed the problem.

For the record, this is PHP 5.2.0 on Apache 1.3.37 using the mod_php interface.

Update 2: Simpler fix just removes the if.. statement and else… section so that it’s just the following:

@header("HTTP/1.1 $header $text");

Bug reported as Ticket 3528.

Continue reading →