Looks like starting from the Google Chrome 63 loading self-signed crx file fails with a message: "This extension may have been corrupted". From the browser logs I see that Chrome is trying to check the verified contents from the store, and, of course, failing.
content_hash_fetcher.cc(252)] Missing verified contents for cfbklnofppkbgcfhppceodfodekoecoa, fetching...
job failed for cfbklnofppkbgcfhppceodfodekoecoa reason:1
VerifyFailed cfbklnofppkbgcfhppceodfodekoecoa reason:1
That's happening for all extensions I can check. Self-signed crx were disabled on reloading Chrome for a while now, but that was mostly OK for basic testing. Now it seems to be not possible at all. Is there a way to install extensions for testing on Chrome 63?
Installing unpacked extensions works (for now), but that's not the same as installing crx. We had some issues which were not happening with unpacked extensions, mostly with init and storages.
UPD: the issue is tracked here https://bugs.chromium.org/p/chromium/issues/detail?id=794219