When selecting text in Konsole (or Yakuake) and right clicking -> Search for xxx with -> Google, two tabs are opened in Chromium (my default browser) and both tabs load the correct search results. The same thing happens with other search engines. Of course the correct behavior is for only one tab to be opened with the search results.
I saw a similar issue if I set the default web browser in KDE5 version of systemsettings -> Applications -> Default Applications -> Web browser to: /usr/bin/firefox %u removing the %u part makes it behave as expect, i.e. only opening one tab.
That fixes it for me, but I'm sure I added that %u at some time in the past to fix another issue with links not opening from other applications. However, I tested a link in Thunderbird and it opened correctly, so I think we can close this bug.
(In reply to Greg Lepore from comment #2) > That fixes it for me, but I'm sure I added that %u at some time in the past > to fix another issue with links not opening from other applications. Yep, I remember something like that with KDE4. > However, I tested a link in Thunderbird and it opened correctly, so I think > we can close this bug. I am not sure Thunderbird actually checks/respects KDE settings; I think it rather uses whatever handler is set for: x-scheme-handler/http x-scheme-handler/https in e.g. ~/.local/share/applications/mimeapps.list (or using xdg-settings, but with xdg-settings you must also set text/html to the same handler or xdg-settings will fail silently... sorry for blathering).
Reopen if still have issues