Sailfish WebEngine: Certificate expiration on old devices (like Sony X)

The support for the old Sony Xperia X has ended. So this is not an official bug and more a question.

On Sony Xperia X (or other older devices): When starting an app with an integrated Sailfish WebView the console shows:

console.error: services.settings:
main/hijack-blocklists Signature failed InvalidSignatureError: Invalid content signature (main/hijack-blocklists)
console.error: services.settings:
main/url-classifier-skip-urls Signature failed InvalidSignatureError: Invalid content signature (main/url-classifier-skip-urls)
console.error: services.settings:
main/hijack-blocklists local data was corrupted
console.warn: services.settings: main/hijack-blocklists Signature verified failed. Retry from scratch
console.error: services.settings:
main/url-classifier-skip-urls local data was corrupted
console.warn: services.settings: main/url-classifier-skip-urls Signature verified failed. Retry from scratch
console.error: services.settings:
main/url-classifier-skip-urls Signature failed again InvalidSignatureError: Invalid content signature (main/url-classifier-skip-urls)
console.error: services.settings:
main/hijack-blocklists Signature failed again InvalidSignatureError: Invalid content signature (main/hijack-blocklists)

As we see the SFOS WebEngine try at start to load some lists from Mozilla (Is this documented elsewhere?). But on devices w/o updates the needed certificate expired ??

Any hints? Thanks.

PS: Mozilla has a big warning a root certificate will expire at Mar 14. Thats tomorrow (at the moment of writing here) and is another story…

IIRC early versions of SFOS 5.0 had this too.

The fix should be somewhere in git but I fear applying it would require a rebuild of the browser which is not trivial.