I used to love Postbox until the latest 6th version.
Sure, they've - allegedly - made it run faster but they've also removed extension support, blocked any ways to hack in a calendar (which could previously be done by adding a permanent browser tab pointing to Google Calendar) and seriously hurt legibility with its new design by removing dividing lines, decreasing contrast across the board and giving all the icons a bright random colour.
Searching in postbox is absolutely horrible. It will regularly not find the emails i am searching for and i have to go through all emails one-by-one.
Last example of today: Filtering emails whether they have an attachment. A mail with attachments i was searching for was not included in the selection.
Sure, they've - allegedly - made it run faster but they've also removed extension support, blocked any ways to hack in a calendar (which could previously be done by adding a permanent browser tab pointing to Google Calendar) and seriously hurt legibility with its new design by removing dividing lines, decreasing contrast across the board and giving all the icons a bright random colour.
A real shame as there are no real alternatives.