jekyll's bundler can't install dependency (Ruby)

Hello, The packages rubygem-jekyll and rubygem-bundler installed without visible errors and the initial "jekyll new " worked too. But "bundle exec jekyll serve" results in this error: Could not find gem 'tzinfo (~> 1.2)' in any of the gem sources listed in your Gemfile. Run `bundle install` to i

gsetting not taking effect

Hello, on Gnome (with Xorg) on Fedora 30 I found that "org.gnome.shell.window-switcher current-workspace-only" is already active by default. I wanted to enable that ALT+TAB only shows tasks from the current workspace. What do I need to do? Greetings, Patrick.