Bugs and issues with subtitles download dialogue

Description

The "Download subtitles" dialogue in the video player is full of bugs and flaws. At the moment, the user experience feels buggy, inconvenient, laborious. It's not a joy to use this feature. Hopefully, the numerous problems can be fixed and improvements can be made. To get a quick overview of the problems, take a look at the screenshots below.

Problems

App behaviour

There is a bug that the open download dialogue is duplicated whenever the screen orientation changes. This shouldn't happen.
This behaviour becomes evident from the shadows around the dialogues. If there are duplicates, it's visible that the shadows become darker as they increase in number. The amount of open duplicates can be counted when they are closed by tapping outside the dialogue. To be exact, the number of open dialogues doubles every time the screen orientation is changed. (Obviously, there is one dialogue in the start. 1st screen rotation: 2 dialogues, 2nd rotation: 4 dialogues, 3rd rotation: 8 dialogues, etc.) All the open dialogues show exactly the same information, even if it's only changed in one of them. If the user types in one text field or activates the search, then closes this dialogue, all other dialogues are in exactly the same state as the closed one.
In the "Episode" text field, the return button of the keyboard performs the wrong action. It should be called "Go" and is supposed to active the search, close the keyboard and scroll down to the results.
Instead, the return key scrolls down but doesn't search. The user is forced to perform two additional, unnecessary steps to manually scroll up again and tap search. In result, the return key is not a shortcut, it is more effort to use. In addition, the keyboard doesn't close in portrait mode although the text field becomes unfocused. So the keyboard is useless anyway but stays open. Currently, the return key is called "Done", which is not the standard for performing a search action. F.e. in browser address bars and in search fields on websites, there is commonly a return key called "Go".
In the "Name" text field, the keyboard has a "Next" button as its return button. It leads to the second field. The "Season" text field though uses a "Done" button. It should use the "Next" button as well, to allow the user to consecutively go through the all three text fields.
This flaw is especially inconvenient because the "Done" button scrolls down, so the user is forced to scroll up again before they can manually go to the next text field.

Visual issues

On the language picker, there should be a space between a comma and the next word.

In portrait mode, the title of the "DOWNLOAD" tab is separated into two lines. The headings of all tabs should fit in one line as the design would look better.

In the "Delete subtitle" dialogue, the space between both buttons is missing. In addition, by convention the buttons should be called "Cancel" and "Delete" instead of "No" and "Yes" in this context. That's clearer. Also, the question in the title should end with a question mark "Delete subtitles?"
(https://material.io/components/dialogs
https://material.io/components/dialogs#actions
https://material.io/components/dialogs#alert-dialog
https://material.io/components/dialogs#specs)
The arrow icon of the languages menu is visible through the tab and the title bar of the dialogue. It should be in the background, behind both bars.
The behaviour of the icon is really buggy when it is behind these bars. It flickers through the layer that should be in front of it while scrolling. It can get stuck in the wrong position, then it's visible twice.
The bottom border of the dialogue below the "DONE" button is thicker than the border to the right of it. Also the border between the button and the search results area is too thick. The borders on all sides of the "DONE" button and the dialogue should have the same thickness. All in all, the button is useless and could be removed.
The design is bad, it's inconsistent and takes up more space than necessary. Especially in landscape mode it is inconvenient. The button has no funcionality. Subtitles are added by when they are touched. There is no abort functionality, so it's not necessary to confirm with a "Done" button. The "Done" button just closes the dialogue, this can simply be done by tapping outside tha dialogue.
The language dialogue uses a bigger, highlighted "DONE" button. It should use the same button as the download dialogue.
There is no point in using a different design in this dialogue. Again, it is inconsistent and the button takes up more space than necessary in landscape mode.
The shadow is not placed symmetrically around the dialogue. It should have the same thickness on all borders.
At the top of the dialogue, it's thinner than at the sides. At the bottom it's thicker. This becomes evident making use of the very first bug described above.

Screenshots

App behaviour

many open duplicates of the dialogue at once
no search performed after using "Done" on the keyboard from the "Episode" text field
missing "Next" button on the keyboard to jump to the "Episode" text field

Visual issues

missing space between more than one language
title of the "DOWNLOAD" tab is separated into two lines in portrait mode:
video player

file browser
missing space between both buttons, wrong button text (by convention: "Cancel" and "Delete")
bug with the arrow of the drop down menu
upper and lower border of the useless bar with the "DONE" button are too thick
inconsistent design, button in the languages dialogue is bigger and highlighted
shadow at the top is too thin, at the bottom it's to thick