See https://support.mozilla.org/en-US/questions/1427439

Also, Compact Headers add-on.

Added CH add on, no change, did nothing. No idea what or where cards view is hidden. Not listed in my View folder and sub folders that I can find.

The attached picture shows the Header Pane when Compact Headers is set to show single-line headers (right-click the pane for options). It also shows the icon next to the Quick Filter button to select Table or Cards view. Enable the Message List Header under View/Layout to show the icon.

I don't think you're getting what I'm trying to fix. It's not the font size of the headers or any other menu item. It's the inability to drag the border between the message list, and the current message being viewed upwards, so that the message list is only 3 or 4 messages deep vertically, leaving the majority of the screen area below it allocated to the currently chosen viewed message from the list. This while I'm using the Classic View window pane option. It currently can't be dragged upwards indefinitely, which would solve my problem. I'm forced to see 9.5 messages in the upper message list area. If I only have 3 or 4 messages in any folder's list, there's a 5+ line gap (wasted screen space) below them until the border/divider is reached. This also means that I'm only able to view 5 or 6 lines of text in any selected/viewed message, with the header displayed at the top of the currently viewed message. How can I post a screen print to the forum, to display an example of what I'm talking about? It's in .jpg format.

See the attached screen print with text on top of the dividing border that I want to be able to adjust farther upwards by drag and drop.

There is an 'add images' below the area where text is entered on the forum. I have seen many comments here on that issue with classic view. I just posted a bug report on bugzilla about this.

A decision was made by the UX folk that the message list space would by enforced as a larger window with the 115 release. Sorry you don't like it, but it is hard coded into the application and is not something that is user configurable.

There is a feedback forum on the Thunderbird help menu. I suggest you use it if you disagree with their decision. You certainly would not be alone.

Hi david, yes, thanks, I figured that out and posted my screen print image. It was a Homer Simpson "doh" moment for me.

Matt, I'll have a look. Thanks for the update on the "new and improved" (not!) T-Bird version's forced feeding crappy, non-user adjustable, page views. Another example of "one size fits all" technology, that doesn't. Makes me want to look elsewhere for a simpler POP email client handler.

I don't think you're getting what I'm trying to fix. It's not the font size of the headers or any other menu item. It's the inability to drag the border between the message list, and the current message being viewed upwards, so that the message list is only 3 or 4 messages deep vertically, leaving the majority of the screen area below it allocated to the currently chosen viewed message from the list. This while I'm using the Classic View window pane option. It currently can't be dragged upwards indefinitely, which would solve my problem. I'm forced to see 9.5 messages in the upper message list area. If I only have 3 or 4 messages in any folder's list, there's a 5+ line gap (wasted screen space) below them until the border/divider is reached. This also means that I'm only able to view 5 or 6 lines of text in any selected/viewed message, with the header displayed at the top of the currently viewed message. How can I post a screen print to the forum, to display an example of what I'm talking about? It's in .jpg format.

Did you read the content in the link in my first reply? It explains a simple method to reduce the minimum height of the message list.

Yes, I read it yesterday when I first started trying to see if there was a simpl(er) config edit parm that could be tweaked like a registry edit tweak for Windows issues, and it made no sense to me then, either. I have no idea what "card" mode is or where it's found, and I don't care. I'm not a programmer, so CSS is what exactly, again? Programmer techno-babble. If I attempted that option, I'd probably do more harm than good, so nope not gonna happen.

So, thanks for trying. I'm clearly not up to your level of expertise for a solution to something that the code crushers at Mozilla changed in a much more useful version of T-Bird, for no useful reason that I can surmise.

Forget about CSS then, even though it is no less difficult nor riskier than registry changes.

Compact Headers add-on is dead easy and works.

Card view would only be helpful if you changed over to View > Layout > Vertical, which would give you the full screen height to display each message. Step by step is at https://support.mozilla.org/en-US/kb/thunderbird-115-supernova-faq#w_how-do-i-get-the-thunderbird-115-supernova-look

i tried CH yesterday and it did nothing. My Classic View page did not change. As I tried to explain it isn't the header size that's the problem.. I've been doing regedits for years and am familiar with it, and the damage it can do. I'd be flying blind trying to do CSS coding, so no thank you.