When extension CodeMirror is activated the key combination Alt+Left jumps like key Home to the beginning of the paragraph and Alt-Right jumps like key End to the end of the paragraph. The redefining of Alt+Left and Alt+Right is annoying because this key combination is normally browser history back and forward.
Please deactivate the redefinition of Alt+Left and Alt+Right in CodeMirror.
Change 373624 had a related patch set uploaded (by Fomafix; owner: Fomafix):
[mediawiki/extensions/CodeMirror@master] Do not redefine the browser history navigation keys Alt-Left and Alt-Right
Change 373624 merged by jenkins-bot:
[mediawiki/extensions/CodeMirror@master] Do not redefine the browser history navigation keys Alt-Left and Alt-Right
Change 377302 had a related patch set uploaded (by Pastakhov; owner: Pastakhov):
[mediawiki/extensions/CodeMirror@master] Fix word jumping (option arrow key) for Mac
Change 377302 merged by jenkins-bot:
[mediawiki/extensions/CodeMirror@master] Fix word jumping (option arrow key) for Mac