It doesn't matter what you have done at second step, in any case it will give you the source editor.
It seems to work for me.
What you describe sounds like the visual editor is not loading because it thinks your browser is unsupported. Do you have JavaScript disabled, or a browser on which MediaWiki does not support JavaScript (like Internet Explorer 8 or before)? If you go to the preferences page to enable the visual editor does it say "This feature requires JavaScript."?
Thanks for your response, @Jdforrester-WMF ․
Can you restore all default settings in hywiktionary, please?
I don't think so :/ because I use VisualEditor in other wikis with the same browser (Google Chrome Version 54.0.2840.99 m or Opera 41.0.2353.69). I have disabled all scripts from Մասնակից:ԱշոտՏՆՂ/common.js and Gadgets from Preferences. But VisualEditor tab doesn't work. BTW, I can use VisualEditor with "Switch to visual editing" bottom on the right corner.