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- [ ] Have you checked if problem occurs with [fish 2.3.1](/fish-shell/fish-shell/releases/tag/2.3.1)?
- [ ] Tried fish without third-party customizations *(check `sh -c 'env HOME=$(mktemp -d) fish'`)*?

**fish version installed** *(`fish --version`)*:

**OS/terminal used**: 

Talk about the the issue here. 

## Reproduction steps
Hard to explain? Link to [a screen recording](https://asciinema.org)

1. Launch fish
2. …

## Expected results
Fish should…

## Actual results
	~ $ math 2 + 2
	5