SUMMARY SHA1 is insecure - but the only authentication method available in KDE Connect STEPS TO REPRODUCE Example of brokenness ob SHA1: https://sha-mbles.github.io/ https://hackaday.com/2017/02/23/shattered-sha-1-is-broken/ SOFTWARE/OS VERSIONS All systems
SHA1 is not used for any cryptographic authentication, it is merely used to generate a somewhat human-readable version of the other device's certificate
Modern KDE Connect versions use SHA256. I suggest someone close this.