`lt-mirror` querySelector cannot penetrate shadowRoot

[13thKID]

Hi!

We've encountered the problem when the LanguageTool plugin is on. We're building our website using web-components (LitElement to be specific) and we noticed, that for some specific scenarios, the lt-mirror elements, cannot be connected with their consecutive inputs.

In the executor.js file, I read that at some point the following line is executed:

document.querySelectorAll("lt-mirror:not([data-lt-linked]), lt-highlighter:not([data-lt-linked])")

,which then connects the lt-mirror elements with the inputs if I'm interpretting the code correctly

However, in the presence of shadowRoot, the selector shown above won't work, which causes those lt-mirror elements to stay "unconnected" (it's worth adding, that it happens when the content is not slotted to the shadowRoot, but rather wrapped inside)

In other words, when the input is wrapped (not slotted) in the shadowRoot, there's data-lt-linked attribute missing in lt-mirror, which does not happen if the content is slotted:

Hopefully this clarifies the problem