"Page translation" tab doesn't show up when the page finishes loading

[WofWca]

Reproduction

1. Open some website in a new tab
2. Before the page finishes loading, click on the extension's icon to open the popup
3. Only the "text translation" tab should be present at this point, which is (somewhat?) normal.
4. Wait until the page finishes loading.

Expected behavior: the "Page translation" tab shows up as soon as possible (at least when the page finishes loading)
Actual behavior: the "Page translation" tab doesn't show up. You have to re-open the popup to see it.

Additional info

In my extension I have this code that is responsible for waiting for a tab to load (I'm not saying it's ideally written though).

Related: #345, #341

[vitonsky]

Duplicate of #268

Popup must listen an event that page must emit while loaded, by this event popup must be re-rendered with new tab, but tab must not be changed.

We have to keep id of active tab on the top component, for a smooth implementation of described behavior