Hi, while migrating to linux mint, I had to configure my multiple mailboxes at the new laptop and OS in TB. TB under linux looks very similar to TB under W10, but not 1-on-1. I use POP3. ver. 140.10.1esr (64-bits) Mozilla Thunderbird Flatpak en-USthunderbird-flatpak - 1.0 My internet provider (ISP) has different mailbox setttings compared to the default thunderbird settings. And I have multiple mailboxes. What really struck me was "the nuisance of hand-set values being overwritten by default settings" by TB. Working from top to bottom through the input screen, many many times these previously inserted manual settings somewhere UP, were overruled when a setting LOWER in the field was toggled. (If it was n´t so annoying you may have liked it as a variation on wack-a-mole. ) It took me hours and hours to find out where things went wrong, and this glitch resulted in hours and hours over and over checking and checking. Also, what does not help, is the error message by TB, when the mailbox settings test is not succesfull. It is just a blank message, without a discription of the error. - 1 Please make manual input overriding/priority to default settings, *especially* when entered in the logical following order of the inputfields in the screen. Dont mess with the lines higher up! Input in a field lower in the screen, may NOT toggle a field to default settings higher up in the screen!!! - 2 I noticed at one instance when the test was succesfull and the mailbox filled with downloaded mails, but the setting for SMTP was not right (test passed okay) and the message would not sent. There was no error message on the configuration of the SMTP, and there was no error messae when sending. Finally it appeared the port was not in the right value. Also, I expected the pop-up window to 'insert the sending password', but that window did not appear, TB did not get tot that part of the code? -3 Ad a short clarification to the 'unsuccesfull test'-message for mailbox configuration, for trouble shooting purposes. Thank you in advance.