Wallets import: import failed on windows

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[wallet] Import failed. Invalid file type: application/vnd.ms-excel     cesium-c99d06c8be.js:3:3382

importFromFile https://vincentux.fr/cesium/dist_js/cesium-c99d06c8be.js:3 
fn https://vincentux.fr/cesium/dist_js/vendor-51fa1c654f.js line 21 > Function:4 
onload https://vincentux.fr/cesium/dist_js/cesium-c99d06c8be.js:51 
eval https://vincentux.fr/cesium/dist_js/vendor-51fa1c654f.js:20 
t https://vincentux.fr/cesium/dist_js/vendor-51fa1c654f.js:20 
x https://vincentux.fr/cesium/dist_js/vendor-51fa1c654f.js:20 
eval https://vincentux.fr/cesium/dist_js/vendor-51fa1c654f.js:20 
apply https://vincentux.fr/cesium/dist_js/vendor-51fa1c654f.js:20 
s https://vincentux.fr/cesium/dist_js/vendor-51fa1c654f.js:20 
r https://vincentux.fr/cesium/dist_js/vendor-51fa1c654f.js:18 
n https://vincentux.fr/cesium/dist_js/vendor-51fa1c654f.js:18

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information