To reproduce: visit https://en.wikipedia.org/wiki/The_Fighting_Temeraire, click "Download as PDF" in the sidebar.

You get a file like this:

In some places the positioning of some characters is just entirely messed up. In the worst cases, two characters are mispositioned so badly, their order is swapped:

Additionally, just about every instance of the character "T" is badly kerned, either way too close to or way too far from the neighboring character. Perhaps the main issue is also caused by a kerning problem?