The Text Properties Dialog
You can do a surprising number of things to the text in a text object, and, aside from editing the text itself, you can do them all from the text properties dialog. You can access the text properties dialog by right-clicking on a text object and selecting Properties or by clicking the properties button (the one with the three little dots on it) on a text object's toolbar.
This dialog consists of a series of pages for editing different aspects of a text object. Clicking on different lines in the list on the left side of the dialog will select different pages.
If you check the "Apply changes as soon as I make them" checkbox, any changes you make will be reflected in the text object as soon as you make them. This is not completely conventional behavior for dialog windows, which normally require you to press the "OK" button before showing you your changes. But we hate the blundering around we have to do when we make changes in a dialog but we can't really tell what we've done until we close the dialog - and then we have to relaunch the dialog if it turns out it wasn't what we wanted. It's like flying an airplane by instruments alone: it takes a lot of expertise to do it well, and most people, including us, don't have that kind of expertise. So we added the Apply changes checkbox. We think you'll like it.
If you don't have the "Apply changes as soon as I make them" checkbox checked, changes you make won't take effect until you click the OK or Apply buttons.
Clicking the Cancel button will close the dialog and reverse any changes you've made, unless you've clicked the Apply button; in that case, clicking the Cancel button will still close the dialog, but it will only reverse changes you've made since the last time you clicked the Apply button. The Apply button will be disabled if you've got the "Apply changes as soon as etc." box checked, because your changes will already be getting "applied" as soon as you make them.