Greetings. I would like to offer here an outline of a design by which a user's often-used special characters can be inserted into text at the cost of one click rather than the 5 or more operations that are presently required for the task. The proposal was previously offered on this forum in December 2010 , but I think that the holidays may have interfered. The suggestion is to make recently used special characters available in a new side-bar in some of the wasted space left or right of the text, and arrange that clicking on a symbol in that side-bar inserts it into the text wherever the cursor happened to be. That is a one-click operation. The sidebar should be saved across editing sessions, of course, and it should also be possible to copy the content of the sidebar from one document to another for similar use there. Therefore "recently used" is only the proposed default mode of filling up this sidebar; the user should be able to customize the sidebar in other ways. In connection with shared editing I propose that the sidebar should be a property of a document, not a property of a user.
The proposed one-click mechanism is, I think, superior to the mechanisms presently available, which require 5 or more clicks. The most direct present mechanism uses the standard menu of special characters. In that case, as an example, to insert a special accented Latin character: Insert / Special Characters / Symbol / Latin; then multiple clicks to scroll down the menu, carefully looking for the desired character, then click on the character, then Okay. I make that a minimum of 6 clicks, and it takes substantial mental effort to locate the character among the thousands. The other presently available mechanism involves creating a personalized document that contains special characters only and from which one copies. Without enough screen space to have two Docs side-by-side one will have that document under another tab in the browser. Then, to insert a special character, one click to move to that other tab, one click-and-drag to highlight, one Ctrl-c to copy, another click on the tab to move back to the primary document, and then a Ctrl-v to insert for a total of 5 clicks or click-like operations, plus the effort to maintain the second document (and additional hassle to make the benefit available in connection with shared editing).