reactive doesn't work on SSR. In a vanilla Nuxt project using just @vue/composition-api, isReactive(reactive({})) prints false on server-side but true on client-side.
Reproduction: https://codesandbox.io/s/sweet-dubinsky-ilbt1?file=/pages/index.vue
Linked issue: https://github.com/nuxt-community/composition-api/issues/244
Did some rough research, this probably becomes the obj return by observe function does not contain the __ob__ attribute. The newly introduced getRegisteredVueOrDefault imports vue by using require, I guess it might be the wrong build for SSR.Vue.observable({}) does not ship with __ob__ attribute in SSR.
I am not familiar with SSR, if someone has any idea of this, please let us know. Thanks.
Simplified problem source reproduce:
https://codesandbox.io/s/vue-observable-ssr-cjmpm?file=/pages/index.vue
Found a workaround in #546