I guess not. For most landlords 1 or 2 months without any income is just bad luck.

If we have recession and travel restrictions for a few quarters prices will fall but still, it is just temporary.

You can expect bubble to pop only if there is some change. For example Work From Home becomes a standard and in results there is systematic outflow from urban centers. Or there is long period of inflation and the capital finds better returns elsewhere. Or 25% of population dies.

So I would say there is a chance of housing bubble popping up but it is not a base scenario.

Yes, but I can easily see the borders staying closed for quite some time, especially in countries that manage to flatten the curve, the direction in which they are closed might change though.