In the Task manager widget of the Panel, can i get it to not show the application titles, but only the icons? I don't see that option when i go to Task Manager Options. So, in this example, i would want only the logo of Firefox, without the "Ask a Question...".
To have only icons instead of icons plus text, first click on the icon boxed in the lower right corner of the image below. (The icon may appear as three parallel bars ☰.) Clicking this icon brings up an interface that allows you to change the location and dimensions of your panel as well as to add/remove widgets.
(I should mention that you'll see the ☰ icon only if you've not locked your widgets. If you don't see the ☰ icon, that means you've locked your widgets and so can't add or remove widgets, or alter the state of your panel(s). Anyway, you can easily toggle between having your widgets locked or unlocked by pressing Alt+D and then pressing L but this has to be done directly on the desktop and not over any window that is in focus.)
Next, click on Add Widgets and, in the search box of the window that appears, type icon, or just scroll up/down until you see the appropriate widget:
Double-click1 on the widget and then close the Add Widgets window. You'll now see both the conventional task manager (showing icons plus text) as well as the icons-only task manager (boxed in yellow) in the image below.
To remove the conventional task manager (showing icons plus text), again click on the the icon that allows you to configure your panel and add widgets. Hover over the area of the conventional task manager and choose Remove. Then, hover over the the icons-only task manager area and drag the task manager to where you want it.
In the image below, we have Firefox, Konsole, Kate and Dolphin all as icons only.
Caution: Although I have been using the icons-only task manager without issue, I've read that some widgets can be resource-heavy or cause memory leakage.
1: There probably are several videos dealing with the same subject. One is Opensuse 42.2 Icon Only Task Manager. Despite the title, it is largely applicable to Kubuntu with KDE Plasma 5.x as well and shows a drag-and-drop route to insert the widget in your panel exactly where you want it saving the effort of subsequently moving it. As with other resources, please make sure the resource matches your version of KDE Plasma.