Mystery WordPress/Markdown Problem: Troubleshooting [en]

[fr] Description d'un vilain problème WordPress avec PHP Markdown Extra. Certains billets refusaient de s'afficher et faisaient tout simplement planter la suite du chargement de la page (donc, pages archives incomplètes, billets disparus). J'ai résolu (plus ou moins) le problème en remplçant PHP Markdown Extra par Markdown tout court, mais je n'ai toujours pas compris le fond du problème. Ce billet donne quelques détails sur les symptômes et mes déductions.

If you’re a WordPress person and you feel like a bit of juicy troubleshooting, this one is for you. I’ve narrowed down part of the problem, but have failed to identify clearly the cause of the problem. I’ve found a workaround by replacing a plugin by another similar one, however. I’ve [made screenshots]( so that even once this problem is fixed (hopefully very quickly) you can make sense of this post.


Some posts on the [VibrationsMusic]( website fail to display their content, or display incompletely. When this happens, the page stops loading altogether, resulting in a truncated page. (So we have vanishing posts and [incomplete aborted archive pages]( where they should appear.) No error messages in source, HTML code just stops.

**Narrowing it down:**

Removing post content makes the post display OK, so I figured it had something to do with the content. Removing the [PHP Markdown Extra plugin]( removed the problem, to. So it has something to do with a combination of certain things in the content and the PHP Markdown Extra plugin. (Removing other plugins didn’t change a thing, so I deduce from that it isn’t a plugin interaction issue.)

Using the “cut-half-out” technique I tried to narrow down the problem to a certain type of post content. At first, it seemed to be caused by either (a) HTML links in Markdown lists or (b) embedded YouTube players (<object>). However, some posts with either (a) or (b) were displaying correctly. In one faulty post, replacing the embedded YouTube video with another removed the problem.

However, it seems more subtle than that. In some cases, removing the *other* half of the post also removes the problem. => post length? Not really either. In a quite weird case, one post [stops displaying right at the end of the content]( (Technorati tags and closing divs don’t appear) and if changes are made to the **next** post (like removing its content) [then the **first** post displays correctly]( (and the second one too).

This seems (to me) to point to some problem in the query-array-manipulation area (but I don’t know how things work well enough in that department to make a more precise hypothesis).


I replaced the PHP Markdown Extra plugin with the [“normal” Markdown plugin](, and everything displays fine.

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Trying WPMU [en]

[fr] Très bref compte-rendu de mon installation de WordPress multi-utilisateurs, la version sous laquelle tourne, qui existe d'ailleurs maintenant en français. Jetez-vous dessus!

I gave [WordPress Multi-User]( a try (that’s the version of WordPress that runs on). Took me roughly half an hour to install from start to finish, then about an hour or two of diluted DNS/vhost troubleshooting until I was told to add ServerAlias * to the vhost file.

I installed the [theme pack](, and I think I got my [technorati tags]( and [basic bilingual]( plugins working (not 100% sure because I haven’t tried using the template tags yet). [PHP Markdown Extra]( works but only if you activate it at blog-level.

I have great ideas about creating a “bunny-approved” package of WPMU now 🙂

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Kit d'installation de WordPress en français [fr]

Quelques liens et instructions très sommaires (un pense-bête, plutôt) pour installer Wordpress en français.

[en] A few links and very brief instructions to install WordPress in French "my way".

Avertissement: WordPress 2.0 sort bientôt, et la suggestion présentée ici sera très certainement caduque à  ce moment-là .

Il vous faut:

– le “pack” [Wordpress en français (]( ([instructions](
– [Spam Karma 2]( ([instructions](
– [Bad Behavior]( ([instructions](
– la documentation française sur la [syntaxe Markdown](
– un [joli thème]( (qu’il faudra peut-être [traduire]( “Un petit nombre le sont déjà …”)) — ou au moins le [Kubrick header generator]( si vous décidez de garder le thème par défaut
– [Un plugin pour les tags](

Côté réglages:

– chmod 775 (ou 777, j’ai un doute) sur le répertoire wp-content/plugins ainsi que wp-content/themes
– uploader un .htaccess vide, chmod 777
– dans les options, copier-coller l’exemple donné pour les permaliens
– activer le plugin Markdown (et les autres plugins qu’on a installés)

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