It's been quite a while, several years in fact, since ProfitUI Target and Implied Target icons were resizable. It happened when effects with "stacks" (effect counters superimposed over the icon) were implemented. At that time you could use the slidebars in the Control Center to resize the icons, and it would work -- until you targeted something else.
So the net result was that all custom Target and Implied Target windows had to revert back to the original default of 15 pixels. On today's higher-resolution displays, that can be very hard to see especially during encounters where the tiny stack counters are relevant.
Some time after the change was made I discovered the solution for DarqUI, and by request the same fix has just been added to ProfitUI CE. Check for updates with the ProfitUI_CE Utility and give the new/old customization setting a try. Also note that both windows can now be resized horizontally if desired. Everything else is as close as possible to standard ProfitUI, because I know as a rule you folks dislike having your UI tinkered with.
There are two ways to enlarge Target/Implied icons: Use the slidebars in the Control Center (see image), which will resize them temporarily just for this session, or edit the settings file to permanently set a custom icon size. You'll notice that the slidebars track each other when used, and it is suggested that you choose the same value for both windows if you customize to something other than the default of 15 pixels.
The configuration file you want is _ProfitUI_Settings_EffectsIconSizes.txt. You only need to change the two values highlighted below. Valid values are between 15 and 48 pixels. If you change the settings, remember to go back and "Skip" that file so the updater won't overwrite it.

I want to thank Darq Side member Myxx who graciously tested and provided feedback while the feature was being worked on.
If you would like to see other ProfitUI CE updates I encourage you to comment here or on our Discord server, and you are always welcome to join us on the Darq Side.