Update: I have since noticed that this is font-specific. It happens with Liberation Mono Regular and Nimbus Mono L Regular, but not any of the other (mono) fonts I have (only tried the regular variants - pressed for time).
- Bug#882028: gedit: utf-8 combinator chars displayed at wrong positi... jnqnfe
- Bug#882028: gedit: utf-8 combinator chars displayed at wrong p... jnqnfe