Question

I have a client that has just moved a very larger, well established wordpress site to a new host. He has a series of JSON api’s delivered via a plugin that have stopped validating (killing a mobile app).

I’ve identified the problem as that after the tags <a or <img are used in the WP admin, a mysterious line break is added. Its not present in the WP html wyswig — but the html src for the page also has the line break.

I’ve tried the following:

• replace: \n, \r, \r\n, char(10) (in various orders) — No change
• replace: different char(#) — No change
• using BBEdit to Zap Gremlins — No change
• opening in VI to make sure that the line breaks are part of the file (they are – $ everywhere)

I’m open to suggestions on a method either identifying and removing these annoyances.

UPDATE: After typing this all out, I realized I should check using a HexEditor. The character is 0A.

EDIT: Edited because part of my question was poorly formatted. The character is being added previous to the JSON output.

Answer 1

After much testing I outlined every known fact:

• It was not legacy,
• Deactivating all plugins did not resolve,
• It was not a rewrite rule,
• It was not garbage in – garbage out…
• It was repeating the issues on a child blog on the same wp build,
• a document at the root did not exhibit this behavior,
• it appeared to happen before rendering but after json_encode,
• it only happened for specific HTML tags (img, a, div, span (actually tags that have attributes like href or class))

After all that we decided that it had to be a plug-in and went through another round of checks.

It turned out to be the plugin wp-minify combined poor testing during the deactivation check. The response was being cached and I assumed that there was no change.