id,node_id,number,title,user,state,locked,assignee,milestone,comments,created_at,updated_at,closed_at,author_association,active_lock_reason,draft,pull_request,body,reactions,performed_via_github_app,state_reason,repo,type
636200235,MDU6SXNzdWU2MzYyMDAyMzU=,4137,set_boundary removes data from axis on faceting plots,3332539,open,0,,,6,2020-06-10T12:20:29Z,2022-04-18T21:43:56Z,,NONE,,,,"I experienced that when using FacetGrid plots and if I want to apply a boundary to the axes, the data from the plots get removed.

A short example to illustrate this:

```python
import xarray as xr
import matplotlib.path as mpath
import cartopy.crs as ccrs
import cartopy.feature as cfeature
import numpy as np

ds = xr.tutorial.load_dataset('air_temperature')

data = ds.air.isel(time=range(0,2))
p = data.plot(transform=ccrs.PlateCarree(),
            y=""lat"", x=""lon"",
            col='time', col_wrap=2,
            subplot_kws={'projection': ccrs.NorthPolarStereo()}
)

theta = np.linspace(0, 2*np.pi, 100)
center, radius = [0.5, 0.5], 0.5
verts = np.vstack([np.sin(theta), np.cos(theta)]).T
circle = mpath.Path(verts * radius + center)

for ax in p.axes.flat:
    ax.coastlines()
    ax.gridlines()
    ax.set_extent([-180,180, 50,90], crs=ccrs.PlateCarree())
    #ax.set_boundary(circle, transform=ax.transAxes)
```
With the last line I want to have a circle as a boundary of each axis. This works but the data are not shown anymore:
<p align=""center"">
<img src=""https://user-images.githubusercontent.com/3332539/84370580-bbc8b500-abd8-11ea-870b-a0811e5e3f26.png"">
</p>
Commenting the last line in the example shows the data as expected but without the boundary of course:
<p align=""center"">
<img src=""https://user-images.githubusercontent.com/3332539/84370766-04806e00-abd9-11ea-94d7-fa44d0e072d7.png"">
</p>

Any hints on why this isn't working?

Cheers,
Markus","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/4137/reactions"", ""total_count"": 1, ""+1"": 1, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,,13221727,issue