搜尋 Mozilla 技術支援網站

防止技術支援詐騙。我們絕對不會要求您撥打電話或發送簡訊,或是提供個人資訊。請用「回報濫用」功能回報可疑的行為。

了解更多

How to block embedded OR attached jpg images from automatic opening in incoming mail?

  • 5 回覆
  • 2 有這個問題
  • 16 次檢視
  • 最近回覆由 Toad-Hall

more options

Hi everyone, When I get incoming mail to Thunderbird, all jpg and csv files, whether attached by a sender as files or being embedded to the body of an email message by the sender, are opened automatically and are displayed in the very bottom of the email message on my end. I would like to prevent jpg images from automatic opening as described above because jpg images might have viruses. Thank you in advance for your help, Gena.

Hi everyone, When I get incoming mail to Thunderbird, all jpg and csv files, whether attached by a sender as files or being embedded to the body of an email message by the sender, are opened automatically and are displayed in the very bottom of the email message on my end. I would like to prevent jpg images from automatic opening as described above because jpg images might have viruses. Thank you in advance for your help, Gena.

所有回覆 (5)

more options

If you receive attachments and do not want them to display below the actual message. Usually it only displays images and text files. All other files need to be opened in order to see them. To switch this off and stop the auto display: 'View' > deselect 'Display Attachments Inline'

If embedded images contain remote content then they should be automatically blocked. check these are being blocked here: Via Menu Bar 'Tools' > 'Options' > Privacy'

via Mail Toolbar: 'Menu icon' > Options' > 'Options' > Privacy'

uncheck 'Allow remote content in messages'. click on 'OK'


Of course you can always view your emails in Plain Text mode which stripes all formatting. Even embedded images will be removed and added as an attachment. 'View' > 'Message Body as' > select 'Plain Text'.

more options

Dear Toad-Hall,

Thank you for your desire to help.

Unfortunately your answer does not address the problem because in my case there is no remote content in images, and your alternative suggestion to view incoming email as Plain Text would remove all html formatting of incoming email messages making them difficult to read (i.e. if they contain tables and other html formatting) in stead of just preventing automatic display of images in incoming mail.

In the event the Forum community believes that the issue I raised cannot be addressed in the current Thunderbird version, then I will kindly ask the Thunderbird developing team to make an enhancement in the forthcoming version of the Thunderbird.

However, before I disturb the Thunderbird developers, I would greatly appreciate any additional input the Forum community may offer towards addressing the said above problem.

Thank you.

more options

So having followed info: 'View' > deselect 'Display Attachments Inline' You no longer see any attachments displayed below message. Only the attachment icon. So this part was successful I presume.

I presume you checked your privacy settings and they are also set to block remote content in images. So this part must also be successful.

This means that you Only seem to be querying embedded (not attached) images that are perfectly good images with no remote content. Please confirm that you want to switch off/disable permanently all displays of all 'embedded' images regardless of whether they have remote content or not.

I'm wondering why you do not like to see images. That is good images that do not have remote content. I think you must be a first to dislike a perfectly ok image but still willing to read in html. Most people complain if perfectly ok images are broken. People who are that concerned about safety usually want all formatting stripped and use Plain Text, hence why I suggested it.

I 'll have alook to see if there is some method of tweaking some settings.

re I would like to prevent jpg images from automatic opening as described above because jpg images might have viruses. I understand your concern about privacy and malware etc. deselect 'Display Attachments Inline' will prevent auto display of attachment images. You do understand that all images with remote content are blocked automatically by thunderbird unless you have made a different selection. Info already provided.

由 Toad-Hall 於 修改

more options

Dear Toad-Hall,

Thank you very much for answering my question in great detail. Deselecting "display attachments inline" did exactly what I need.

Taking in consideration that I am not a software developer. could you please just clarify for me whether jpg images which do not have remote content might have viruses?

I also found an option in View menu: "simle html". If possible, could you please also clarify the difference between "simple html" vs. "original html"?

I have no more questions and hope that clarifications will help me and some other users of Thunderbird to understand better these options.

Best regards and thank you once again for your help,

Gena.

more options

'Simple HTML' is similar to the Original HTML setting but it has been sanitised, so will only interpret basic HTML commands, disables Javascript, and doesn't display remote images.

For example it will ignore 'style sheets' and it will block almost all malicious code while still allowing you to see the normal HTML formatting (bold, colors, images, etc.)

If you have an anti-virus product, this can be set to scan incoming and outgoing messages. However, some people have found this extra process performed by the anti-virus can cause some slowdown in opening and sending mail.

Any attachments will be scanned by the anti-virus when they are opened regardless of whether you scan the actual email or not.

Remote content: It is possible to send an HTML E-mail that loads an image from a remote Web server. The reference to the image could be something other than an image, even though an image is actually displayed in the E-mail.

This could contain variables that the sender want to learn, such as who received the E-mail, and many other variables gathered when the E-mail client loads the "image" from the Web server. They could check their server logs for who is accessing the image from where.

In Thunderbird, remote content (images) are not downloaded by default.

Images that do not contain remote content and are embedded in the content (not attachments) should be ok.

there is always Plain Text mode if unsure. You can always check the source code using View > Message Source.

Checking a link before selecting: You can check all links by hovering mouse cursor over (not clicking) the link and it will display the real link in the bottom Status Bar.

Never assume that an email is from the person it purports to be. Nefarious people do abuse other peoples email addresses.

General reading: http://www.howtogeek.com/135546/htg-explains-why-you-cant-get-infected-just-by-opening-an-email-and-when-you-can/