Took me quite some time to achieve that! I was about to rename the critter Houdini! There was one 60' length which has fairly dense undergrowth against the boundary. At first she was not able to get through it - but eventually found a couple of places. Since there was a post and rail fence behind it, I managed to get through to it and affix some chicken wire. She would then work on getting through to new bits, and I would patch that bit etc. We played that game for weeks until in the end I wired the whole length of fence. I thought aha - that will stop you. So next time she vanished and I was standing out there at dusk wondering where she had gone, I saw this white blur appear in the neighbours paddock, run straight toward the fence, and apparently pass straight though it unhindered! Turns out she worked on wiggling under the bottom of the wire enough so that it stretched and let her through - then just remembered the weak spots. So for the last round I bought a couple of packs of tile batten, and screwed it to the posts along the base of the fence close to the ground, then cable tied the wire to the batten. Not had an escape since then, although she did go and inspect the full length very carefully!
I may have won the last battle - not totally convinced the campaign is fully over yet though.