thunderbird 68: "TypeError: this.asyncConnection is null" on ppc64el

I'm seeing enigmail 2.1.2 autopkgtest failures (only) on ppc64el, with thunderbird 68.0 and 68.1.0.

When running thunderbird in xvfb in a ppc64el VM in the cloud, I'm seeing the following error message printed out several times:

JavaScript error: resource:///modules/gloda/datastore.js, line 1384: TypeError: this.asyncConnection is null

In the context of enigmail autopkgtests, I'm seeing this:

JavaScript error: resource:///modules/gloda/datastore.js, line 1384: TypeError: this.asyncConnection is null
JSUnit starting tests
Starting JS unit tests main.js

success!!!
checkDatabaseStructure
checkDatabaseStructure - success
createTable()
JavaScript error: resource://gre/modules/Sqlite.jsm, line 815: Error: Error(s) encountered during statement execution: database disk image is malformed
JavaScript error: resource://gre/modules/Sqlite.jsm, line 81: Error: Warning: Sqlite connection 'testing.sqlite#0' was not properly closed. Auto-close triggered by garbage collection.

And the tests hang forever until autopkgtest times out.