When the editor is being loaded, there is a very noticeable lag while the various icons are loaded up. The average editor has about twenty separate icons. Each one of those represents a request to the server. Even if the icon is already loaded, the browser makes a request anyway, to see if a newer version is available.
There is one easy way to fix this – get all the icons, paste them all into one large bitmap, and use CSS to display the appropriate cropped part of the bitmap as needed. The unfortunate part of this method is that all icons must be located at predictable locations and have predictable sizes. This could be a mistake, if you want to display the toolbar with different themes, which may have different-sized icons.
But – there’s another way which would be useful for much more than just FCKeditor: what if all the icons were provided in one file as sections of SVG? With SVG, the locations of the icons in the file are not a problem, and the icons are whatever size you want them to be.
So – I believe that SVG may be the answer to the problem.
However, as far as I know, not many browsers natively support SVG. Firefox does recently, and I think Opera does as well, but IE (the most popular one) doesn’t, and even Konqueror, which I’m writing this in, only supports it if you specifically compile it in. (don’t bite my head off if I’ve got something wrong in this paragraph – it’s all voodoo anyway)
Anyway… there y’are. Just an idea. I’m not promising that I’ll do this any time soon, but you never know – I may just sit down and write it. If I’m lucky, I may be able to convince the boss that the project is worthwhile (which it is), and will be allowed to do it during work hours (I’m usually too tired outside of that time to get anything done).