I go to a string property in the property editor. If I type one of certain characters: jklqvxz, as well as numbers and some accented characters, an ampersand character ('&') is automatically inserted before it. Even if I delete it, it gets inserted again.

Other anomalies occur too: for example, if I type "&a", and then hit 'l', it becomes "a&l". If I type "&a&l", it becomes "a&&&l".