`GFiles?` displaying weird characters after using git stash

- [x] I have fzf 0.23.0 or above
- [x] I have read through https://github.com/junegunn/fzf.vim/blob/master/README.md
- [x] I have read through https://github.com/junegunn/fzf/blob/master/README-VIM.md
- [x] I have read through the manual page of fzf (`man fzf`)
- [x] I have searched through the existing issues

Given:
* windows10
* the latest versions of gvim, fzf (0.25.0), fzf/vim/fzf.vim and fzf.vim
* [this](https://stackoverflow.com/questions/57131654/using-utf-8-encoding-chcp-65001-in-command-prompt-windows-powershell-window/57134096#57134096) windows configuration in order to have a default utf8 locale
* a repository that uses 4-spaces indentation style
* a git smudge/clean to have tabs indentation style

When:
* I make a change in a local git repository
* I run `:GFiles?`

`GFiles?` works as expected.

Until I run `!git stash`, `:Git stash` (through vim-fugitive) or `!git stash pop`.

Once I run these commands, the displayed output is filled with weird extra characters and broken layout.

Here are some screenshots:

Before I use a `git stash` (expected behavior). I typed `iiii` in the search bar:

After I used a `git stash` (actual behavior):
* I didn't type anything after `GFiles?`:

* I typed `iiii` in the search bar:

When trying with this minimal vimrc (using `fzf.vim` and `fzf/plugin/fzf.vim`):
```
set nocompatible hidden laststatus=2
filetype plugin indent on
silent! language messages English_United states
```

I couldn't get a good screenshot yet. This is what I have right now with that minimal vimrc:

**Additional notes**:
* `:GFiles`, `:Files` and other commands display correct output
* I will try to get back on this issue later in order to fill more details if needed!