Zathura is a lightweight yes highly customizable PDF reviewer. It works well with Latex.
Recently, I found that its copying text does not well. The solution can be found here.
Primary and Clipboard
In X11, text copying is handled through selections rather than a single clipboard. The PRIMARY selection copies text implicitly when it is selected and is typically pasted using the middle mouse button, making it transient and selection-driven. In contrast, the CLIPBOARD selection requires an explicit copy action (such as Ctrl+C) and is pasted with Ctrl+V, providing a more persistent and familiar copy-paste behavior aligned with modern desktop environments.
Zathura uses Primary as its selection by default.