Reading an Email

[kenmorgan]

When I open an email on Thunderbird, it sometimes doesn't show parts of the email. It prints a message saying that it didn't display those items in order to protect my "privacy." But it does provide a button to click to display the whole email if I want to.

Am I right in concluding the following:

(1) If I do NOT click the button that would display the rest of the email, the sender of the email will have NO WAY to determine whether or not I read his email.

(2) If I DO click the button that displays the rest of the email, the sender of the email WILL KNOW that I read his email.

These questions may be a bit simple to most on this forum, but I just wanted to make sure that my two assumptions are accurate.

If they are not, is there any way to read an email without the sender knowing I READ it?

Even better, can I receive an email without the sender knowing I received it? Or will the sender always know I at least received an email if it does not bounce back to him with some sort of message?

Thanks so much.

Ken

[DanRaisch]

(1) If I do NOT click the button that would display the rest of the email, the sender of the email will have NO WAY to determine whether or not I read his email.

(2) If I DO click the button that displays the rest of the email, the sender of the email WILL KNOW that I read his email.

Probably not and probably not. That functionality has nothing to do with "Return Receipt" or "Read Receipt" function which let the sender know that you've viewed the message. Instead it blocks the display of remote content. That is, material which is not embedded in the message itself is not downloaded to your computer until/unless by clicking on that button you tell Thunderbird to downloaded it. That would include graphics hosted on a remote site, like images in advertising. Some remote content could be malicious and that's why Thunderbird let's the user choose which sites are to be permitted to download and display such things.
If an email is sent to a valid email address there would be no bounce back message to the sender so the sender can (in general) assume that the message at least go to the email server associated with the address. That doesn't mean that a spam filter won't divert the message into a Junk/Spam/Bulk folder on the server as undesirable nor does it mean that a filter on the recipient's computer won't perform that action. Also see this article -- https://support.mozilla.org/en-US/questions/1206804

[sfhowes]

If you want to block all remote content, some of which could be used to verify that you opened the message, and at the same time not have the privacy banner appear, set View/Message Body As to Simple HTML.

[tanstaafl]

http://kb.mozillazine.org/Privacy_basics_-_Thunderbird

The safest way to read a message without anybody knowing it is to set mailnews.message_display.disable_remote_image to false, set view -> message body as -> plain text and restart. However, that can be inconvenient if you sometimes want to display HTML.

I suggest you use the Allow HTML Temp add-on to temporarily display HTML as needed. After you install the add-on and restart Thunderbird you'll need to right click on the main toolbar, select "Customize" from the context menu, drag and drop the "Show HTML" button to the main windows toolbar, and press the "Done" button. Then set view -> message body as -> plain text and whenever you want to see the HTML content of a message press the Show HTML button. It does NOT toggle the view ->message body as setting, so you don't need to worry about the next message being displayed as HTML without your pressing the button again.

I tried it on my PC (using TB 60.4.0 under windows 10) and it seemed to work fine.

[kenmorgan]

Thanks so much to all three of you for your help. I'll be studying the points you made, hopefully tomorrow (Wednesday).

Ken

P.S.: Yukon King gives you his special greetings, Dan.