on the command line (terminal) it shows options to resolve though, it conflicts with one of the newer Firefox 140esr packages it seems.
sudo zypper up MozillaThunderbird
Problem: 1: the installed kmozillahelper-5.0.6-bp156.1.3.x86_64 requires ‘mozilla-kde4-version = 6’, but this requirement cannot be provided
not installable providers: MozillaFirefox-115.10.0-150200.152.134.1.x86_64[https-download.opensuse.org-788d01d4]
…
Solution 1: downgrade of MozillaFirefox-140.1.0-150200.152.193.1.x86_64 to MozillaFirefox-128.12.0-150200.152.188.1.x86_64
Solution 2: deinstallation of kmozillahelper-5.0.6-bp156.1.3.x86_64
Solution 3: do not install MozillaThunderbird-140.1.0-150200.8.230.1.x86_64
Solution 4: break kmozillahelper-5.0.6-bp156.1.3.x86_64 by ignoring some of its dependencies