https://www.quixapp.com/

Is this the bookmarklet?

javascript:Quix();function%20Quix(){var%20e=encodeURIComponent;var%20t=window.getSelection?window.getSelection():(document.getSelection?document.getSelection():(document.selection?document.selection.createRange().text:''));var%20c=window.prompt('Quix:%20Type%20`help`%20for%20a%20list%20of%20commands:');if(t!=''){if(c){c+='%20'+t;}else{c=''+t;}}if(c){var%20u='https://www.quixapp.com/go/?c='+e(c)+'&t='+(document.title?e(document.title):'')+'&s='+'&v=090'+'&u='+(document.location?e(document.location):'');d=''+document.location;if(d.substr(0,4)!='http'){window.location=u+'&mode=direct';}else{heads=document.getElementsByTagName('head');if(c.substring(0,1)=='%20'){var%20w=window.open(u+'&mode=direct');w.focus();}else%20if(heads.length==0){window.location=u+'&mode=direct';}else{q=document.getElementById('quix');if(q){q.parentNode.removeChild(q);}sc=document.createElement('script');sc.src=u;sc.id='quix';sc.type='text/javascript';void(heads[0].appendChild(sc));}}}}

In case one of our JavaScript gurus can figure out why it doesn't work in a blank tab.

https://www.quixapp.com/browsers/firefox/ Have you tried setting up a Hotkey? But that would need this extension, somewhat defeating why a person would use that bookmarklet. https://addons.mozilla.org/en-US/firefox/addon/sitelauncher/

Is that page a disabled about:newtab page?

You would have to set another page as the new tab page to make that work. Bookmarklets do not work on such XML pages.

That is indeed the bookmarklet in question, although mine also has a call to a custom set of commands.

You nailed it, cor-el. If I enter about:newtab in the address field, then the javascript doesn't work. If I then enter about:blank, it works.

Any way to get a new tab to work like a blank?

You can set the new tab page to about:blank by modifying the browser.newtab.url pref on the about:config page.

That fixed it -- many thanks, cor-el!