This is the 4574th most frequent Japanese word.
張り付い
"張り付い" means "to stick" or "to cling" in English.
In this sentence, '張り付いて' refers to something physically adhering, as the bug is stuck to the glass.
ガラスに虫が張り付いている。
A bug is stuck onto the glass.
Here, '張り付いて' metaphorically describes being intensely focused or captivated by the screen, similar to being physically stuck.
彼の目はスクリーンに張り付いて離れなかった。
His eyes were glued to the screen and wouldn't look away.
In this example, '張り付いた' depicts the act of sticking or attaching something specifically, in this case, the poster to the stand.