Well... the jar may explode only if the pressure into it grow stronger enough. If you let a small opening for the excess of pressure escape, there is no risk of the jar explode.

When i make green dragon i use an usual glass and cover it with a dish. The dish avoids excessive evaporation of the alcohol but lets the excess of pressure escape. There is, of course, some loss of alcohol due the evaporation, but it dont seems to be a problem.