agsteele

You can select the default view in settings but it isn't retroactive. It will only affect PDFs added from the date the change is made.
Also, it doesn't affect all ways of adding a PDF. Some PDF import will always default to single page view. (For example using import folders)

This is definitely not the way things should work and I've not seen this.
I'd recommend that you uninstall using Revo Uninstaller. Then download the latest version from Evernote.com and reinstall. The direct download is a better option than the Microsoft store version.
Use Revo Uninstaller since the standard Windows uninstall leaves lots of files behind.
 

Yes. Since the master copy is in the cloud it can always be recovered. The only Legacy notebooks that are not in the cloud are local offline notebooks. These should be exported to ENEX prior to deletion or the contents transferred to an online notebook.

Create a new notebook, make that the default and then delete the note.  But you still have to remember to empty the trash. 
However, deleting the account will delete the data as well so there is no real need to empty the notebooks first.

The limits you are experiencing are fixed and hard. There is no solution other than reducing the number of notes and tags.
It seems that Evernote is not suitable for what you are attempting to do.

Possibly a hiccup in your local data.
I'd rebuild the data on the Windows PC.
File / Sign Out / Remove data
When you log back in the data will be rebuilt over a period.

The affiliate programs is suspended. It isn't clear what, if any, options are being considered. The CJ programme is over and will not be resumed.

When you click the option to reveal the encrypted text the Hint is displayed underneath the box where you type.  If the hint is empty then you did not provide a hint. As you can see I store passwords in a secure storage program.  It compensates for my ever increasing forgettery...

The web clipper uploads pages using standard web protocols. If your company is monitoring web traffic from your browser it will see connection to Evernote.

Yes. Select the notes and the choose move option in the blue tool bar.

No. The website view via a share is a best approximation that can be shown in a simple web page.
The checked items in the list are not simple HTML to display. Neither can they be checked via the shared view.
If you think it should be different I'd recommend you issue a feedback from within the application or open a support ticket.

Thanks for the information. I suspect that you have corrupted local data. First thing to try...
File, Sign Out, Remove data from this device
Sign back in and allow Evernote to rebuild your data from the cloud.
If that doesn't work uninstall Evernote using the Revo Uninstaller program. A default Windows uninstall does not clean out all the data and configuration. Then reinstall from the latest version at www.evernote.com/download
Again, sign back in and allow your data to be rebuilt from the cloud.
 

Exporting a note containing a PDF as a PDF will only display the attached PDF name as you have shared.
If you want to 'export' the attachment then right click and select Open or Save as required. Or you can drag and drop to the desktop or to the File Explorer.

You can disable this keyboard interaction in Evernote.
Open the Keyboard shortcut (Ctrl+/) In the Global section, point with the mouse to hover over the 'Open Evernote Helper' option Select the three dot menu that will appear to the left of this option and select Disable You should find that the AltGr+H  no longer opens the Evernote Helper and is now only doing what you need.  I'm not sure why AltGr and Alt+Ctrl are captured as the same keystroke.  If you want the Evernote Helper you can change the keystrokes to something else via the Edit option.

www.evernote.com/download 

It it's easy to export a notebook containing all it's notes from inside the desktop applications. Select export from the three for menu in the notebook.
Repeat for multiple notebooks or use a third party export program. There are several that you'll find if you seek the forums. I use a Github project called evernote-backup.

I am not having this issue with Firefox. You should probably start with the Firefox help pages at https://support.mozilla.org
Typical suggestions would be to remove all cookies and cache for Evernote.com in Firefox.  Logging back in may then resolve the issue.
Disabling all Firefox Add-Ons and then check if the problem is resolved. If it is then add them back one at a time and see which, if any, recreate the problem.

There are a number of home screen widgets for Android 10. Not entirely the same as V8 so it will depend what you need as to whether you'll be satisfied.
You get
Task list Note list Shortcuts list Action bar You can also save a shortcut to individual notes on the 'desktop' direct from the note editing menus.
The bonus of v10 on Android is that you can use any/all the features and functions across devices.
The issues I see reported with v10 on Android often seem to be with Samsung devices. But that may just be because it is the dominant Android device maker.

Nothing will change other than the limits imposed by being on Free. Any notes which are larger than the maximum permitted by Free will, in effect, be locked. You will be able to view them but not edit them. Otherwise notes will be fully accessible. You will have a lower upload limit and you can only have two devices connected to your account. Before making the switch Is recommend that you check the connected devices in your account settings and disconnect all devices.
You can then limit yourself to only two devices and make the switch. Remember the web access counts as a device along with any desktop or mobile apps.

A good number of reports suggest duplicated notes are a problem for some.
Equally there are many others who say that they never have an issue. (I am one of those).
So there is an issue but there is no consensus on the cause. I can say that I almost always go back to Home on my desktop so no note had focus.
Evernote is currently beta testing a new sync process. The hope is that this will resolve this issue as well as offering new function.

You'd have to go to one of the APK sharing sites such as APK Mirror.

My guess, you have the MacOS Ventura and you are using the Legacy version of Evernote. 
Legacy is doomed to eventually dying. The Ventura OS update has broken Legacy.
It will not be fixed. 
You have the option to upgrade Evernote to v10 or suffer the wider gap.

It could also be some local data corruption. I'd rebuild my local data and see if that resolved the issue.

Yes, I suppose that the purple is less clear in dark mode.  You'll need to suggest this directly to Evernote via Feedback or a support ticket if you require a response.  But don't expect a sudden change.  I'd imagine that this will not get high attention.

Evernote tasks cannot sync with an external program because the API is, yet, to be updated. You can connect via third party applications to check boxes and note reminders but not directly to tasks. Evernote tasks is, currently, a standalone feature.
Outlook calendar sync has proved rather more difficult than you might imagine to integrate with. Google calendar was the first choice, I think, because Evernote uses Google infrastructure and the connections were easier to achieve. There are no timelines ever provided by Evernote but I anticipate Outlook calendar connection within the next three months. But I'm just another user so what do I know?
So far all the integrations are one way. So you can view Google calendar inside Evernote but you cannot update that calendarfrom within Evernote. Expect the same with Outlook when it arrives and also the Apple calendar stuff too.