DataCloneError preventing to load session

[bwindels]

the user reported being unable to load the session, with a DataCloneError in indexeddb-worker.js:1, in the console.

Rageshake logged with mxSendRageshake at https://github.com/matrix-org/riot-web-rageshakes/issues/1625

Also see discussion on riot room: https://matrix.to/#/!iNmaIQExDMeqdITdHH:matrix.org/$1561384523827447zKWph:matrix.org?via=matrix.org&via=privacytools.io&via=librem.one

[t3chguy]

Closing due to lack of repro in 5 years