I confirm that it's slower than expected to open attachments(both pdf and doc documents) on Ubuntu 18.04.

All steps mentioned above have been tried and

<font color="#8AE234">arinya@arinya-HP-ZBook-15u-G5</font>:<font color="#729FCF">~</font>$ lsb_release -a
No LSB modules are available.
Distributor ID:	Ubuntu
Description:	Ubuntu 18.04.3 LTS
Release:	18.04
Codename:	bionic
<font color="#8AE234">arinya@arinya-HP-ZBook-15u-G5</font>:<font color="#729FCF">~</font>$ thunderbird --version
 Thunderbird 68.2.1
<font color="#8AE234">arinya@arinya-HP-ZBook-15u-G5</font>:<font color="#729FCF">~</font>$ 

iamjayakumars said

Make sure, the pdf is downloaded to the system. If its not downloaded, it takes some time to download and open the file. Change your setting to download all the attachment.

When i was using 60.9, i was not having this issue. It opened faster, but the moment i downloaded the new 68. It started taking longer to open the same file.

This is for a mail i had opened before in the previous 60.9.

So, unless i am missing something... can you show me how to check that the PDF has downloaded to the system

I downloaded 60.9.1 from https://ftp.mozilla.org/pub/thunderbird/releases/

it was as slow as ver68.