Acts of resistance come in many shapes and sizes. From a colored ribbon tied to a tree or a flag raised over a remote mountain face, to a quick tip-off on an encrypted app that sets off a chain of events culminating in the destruction of a warship, everything counts. However big or small, whether the impact is military or symbolic, the actions of Ukrainians living in Russian-occupied territories over almost two years of full-scale war have all worked to drive one simple message home: that Russia’s grip on parts of Ukraine is as weak as it is temporary. Around a fifth of Ukraine is occupied by …