BRASCA, 13 12 bytes
1[`/\`1?#$o]
Explanation
1[ ] - While 1:
`/\` - Push \ and /
1? - Push rand(0,1)
#$ - If truthy, swap the top two items, else skip.
o - Print it!
1[`/\`1?#$o]
1[ ] - While 1:
`/\` - Push \ and /
1? - Push rand(0,1)
#$ - If truthy, swap the top two items, else skip.
o - Print it!