Join the AMA (Ask Me Anything) with the Firefox leadership team to celebrate Firefox 20th anniversary and discuss Firefox’s future on Mozilla Connect. Mark your calendar on Thursday, November 14, 18:00 - 20:00 UTC!

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Rohkem teavet

Thunderbird: How to disable message forwarding in base64

  • 2 vastust
  • 2 on selline probleem
  • 1 view
  • Viimati vastas Toad-Hall

more options

Apparently since the Update to Thunderbird 45, HTML-mails get forwarded as base64. Is there any way to disable this and go back to the former behavior without downgrading to 38.x?

For example:


User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101

Thunderbird/45.3.0

MIME-Version: 1.0 In-Reply-To: <...> Content-Type: multipart/alternative;

boundary="------------41543626587C7FD8D269B4D8"

This is a multi-part message in MIME format.


41543626587C7FD8D269B4D8

Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit

...Plaintext...


41543626587C7FD8D269B4D8

Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: base64

...HTML and attachements in base 64...


Apparently since the Update to Thunderbird 45, HTML-mails get forwarded as base64. Is there any way to disable this and go back to the former behavior without downgrading to 38.x? For example: -------------- User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 MIME-Version: 1.0 In-Reply-To: <...> Content-Type: multipart/alternative; boundary="------------41543626587C7FD8D269B4D8" This is a multi-part message in MIME format. --------------41543626587C7FD8D269B4D8 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit ...Plaintext... --------------41543626587C7FD8D269B4D8 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: base64 ...HTML and attachements in base 64... --------------

Valitud lahendus

It would seem you located the answer before I got to this query. Thankyou for reporting back with info. could you mark your own response as 'Chosen Solution'.

As additional info, just in case someone else locates this same query. setting "mail.strictly_mime" to true is done via the 'Config editor' located here: 'Menu icon' > 'Options' > 'Options' >'Advanced' > 'General' tab click on 'Config Editor' button.

Loe vastust kontekstis 👍 0

All Replies (2)

more options

As it seems, setting "mail.strictly_mime" to true, solves my problem.

more options

Valitud lahendus

It would seem you located the answer before I got to this query. Thankyou for reporting back with info. could you mark your own response as 'Chosen Solution'.

As additional info, just in case someone else locates this same query. setting "mail.strictly_mime" to true is done via the 'Config editor' located here: 'Menu icon' > 'Options' > 'Options' >'Advanced' > 'General' tab click on 'Config Editor' button.