This extension is compatible with the themes Mosaic-Fox (version 1.3.5+ only), Internet Exploration, Winestripe RealFox, Firefox 2 theme for Firefox 3.x. Previously planned features were: a) Make it an option to be able to open new tab by Ctrl-T as relative, without running away to the end of the line. b) Make homepage button disabled when the user already is at the homepage. c) In the Downloads window, add 'Properties' in context menu, and 'Open' and 'Remove' links next to each download. The properties menu item will open up the Windows properties display for the file (same as if you right-click on the file in windows explorer and clicked on properties). d) (Firefox4) Add a tick-box for the "devtools.errorconsole.enabled" -- setting it to "true" makes the error console appear. e) (Firefox4) An option to bring the status bar back.
This extension is no longer maintained. Despite the thorough positive feedback, I am no longer maintaining this extension. I discovered a community project called SeaMonkey, powered by the Mozilla platform, and I find that it has all of the philosophy I was after when writing this extension. I list the features Go classic had below, and I indicate replacement extensions to do the job if they are available. (Obviously some of those are not implemented by other people and I might be releasing small separate restartless add-ons which do the job, but getting familiar with that technology could take a while.)
Customise Go button: modify Go-button, including its image - default like in Firefox 1; theme (depends on your theme); inside at the left; none; no changes - leaves the Go button where it was, usually at the right inside of URL-bar; or even a custom Go button image URL. Go button label is always outside of the URL-bar and can be set to either custom or none.
Customise URL-bar label. With URL-bar, you can choose to show or to hide label before URL-bar.
Customise URL-bar feed and star buttons: to show or to hide feed button, to show or to hide star button.
Customise URL-bar auto-complete popup: whether to have a rich autocomplete popup, which is called "awesome bar", or to have "poor" autocomplete popup, which is called "old bar". This job is done by oldbar extension.
Customize Back and Forward menu-list buttons: there can be none (The Firefox default), one (use back/forward dropmarker or noun buttons), two of them, or two with "button + drop-marker" border grouping (SeaMonkey default).
A set of custom toolbar buttons. This extension also adds several previous-century buttons into the "customize toolbar" window, they are "Open File...", "Save Page As...", "Print Preview", "Find on this page...", "Help contents", "News", "Email", "Hide images", "Bookmark this page...", "Subscript to this page...". The style of images of additional toolbar buttons can be set to one of the following: NCSA Mosaic; Firefox 1.0; Windows Classic; OpenOffice Classic; Windows Vista; OpenOffice Galaxy; simple. The "News" and "EMail" buttons simply take you to web-sites of your choice, which can be set in the options window too.
Choose the position of close buttons on tabs: on the active tab only, on all tabs (default), no close buttons, or a single close button at the end of the tab strip (Firefox 1.x behavior).
Choose the prefpanes' arrangement: horizontal (default) or vertical.
New tab button: Show or to hide.
Insert related tab after current: yes/no.
Show "Get addons" pane in Add-ons dialog: yes/no (restart it).
Bring back the "Properties" context-menu-item (Firefox 3.6 and up): yes/no.
Configuration mania is also of interest to the goals and design of this extension. Thanks, Tom!