Windows 10 reached EOS (end of support) on October 14, 2025. If you are on Windows 10, see this article.

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.

Learn More
Open

When you resize the window vertically, the message list resizes and the preview stays fixed, how to keep the list constant height ?

Salon

Hi,

I use AltSnap and its snap feature a lot because I have multiple 40" TVs as monitors.

That means I often deal with thunderbird floating windows rather than maximized, and I often resize it.

And I notice that my message list is always getting too small !

I realized this is because when you resize the thunderbird window vertically, the preview pane stays a constant size, but it is the message list that resizes.

Over time the message list gets squished out and not even one message is visible.

I think if the message list remained of a constant size during vertical resize and it was the preview pane that got resized along with the window, it would prevent that and the message list would always be, the size that you last set it.

Hi, I use AltSnap and its snap feature a lot because I have multiple 40" TVs as monitors. That means I often deal with thunderbird floating windows rather than maximized, and I often resize it. And I notice that my message list is always getting too small ! I realized this is because when you resize the thunderbird window vertically, the preview pane stays a constant size, but it is the message list that resizes. Over time the message list gets squished out and not even one message is visible. I think if the message list remained of a constant size during vertical resize and it was the preview pane that got resized along with the window, it would prevent that and the message list would always be, the size that you last set it.

All Replies (3)

I tried setting

toolkit.legacyUserProfileCustomizations.stylesheets to true in setting->general->config editor

Then I created this folder C:\Users\user\AppData\Roaming\Thunderbird\Profiles\1jujzs1s.default-release\chrome and created this file C:\Users\user\AppData\Roaming\Thunderbird\Profiles\1jujzs1s.default-release\chrome\userChrome.css

First version I tried

@-moz-document url-prefix("about:3pane") {

 #threadPane {
   height: 350px !important;
   min-height: 350px !important;
   max-height: 350px !important;
   flex: 0 0 350px !important;
 }
 #messagePane {
   height: auto !important;
   min-height: 0 !important;
   max-height: none !important;
   flex: 1 1 auto !important;
 }

}

If I shrink window vertically preview pane shrinks, message list stays the same, great ! If I increase the window vertically preview window increases, up to a point then a empty space grows between message list and preview pane !

next I tried

@-moz-document url-prefix("about:3pane") {

 /* Keep the message list at a fixed height. */
 #threadPane {
   flex: 0 0 300px !important;
   height: 300px !important;
   max-height: 300px !important;
 }
 /* Let the message preview absorb window resizing. */
 #messagePane {
   flex: 1 1 auto !important;
   height: auto !important;
   max-height: none !important;
 }

}

but this was like normal, except the preview pane was half the width and the rest was blank

then I tried this

@-moz-document url-prefix("about:3pane") {

 /* Preserve the message-list height when the window shrinks. */
 #threadPane {
   flex-shrink: 0 !important;
 }
 /* Make the preview absorb both shrinking and extra space. */
 #messagePane {
   flex: 1 1 auto !important;
   min-height: 0 !important;
   max-height: none !important;
   height: auto !important;
 }

}

Things are back as they were, message list grows and shrinks, while preview pane stays the same height and only starts to shrink once message list and folder pane are completely squished

next I tried

@-moz-document url-prefix("about:3pane") {

 #threadPane {
   flex-shrink: 0 !important;
 }
 #messagePane,
 #messagePaneWrapper {
   flex-grow: 1 !important;
   flex-shrink: 1 !important;
   min-height: 0 !important;
   max-height: none !important;
   height: auto !important;
 }

}


but it was the same

Ok this version almost works

@-moz-document url-prefix("about:3pane") {

 :root {
   --uc-message-list-height: 350px;
 }
 /*
  * Find the grid containing both the thread pane and message pane.
  * Keep the thread pane fixed; give remaining height to the preview.
  */
 *:has(> #threadPane):has(> #messagePane) {
   grid-template-rows:
     var(--uc-message-list-height)
     auto
     minmax(0, 1fr) !important;
 }
 #threadPane {
   min-height: 0 !important;
   height: auto !important;
   max-height: none !important;
 }
 #messagePane {
   min-height: 0 !important;
   height: auto !important;
   max-height: none !important;
 }

}

The preview/reading pane is what resizes when I resize the window, and the message list stays the same height.

But this version, I can't manually resize the message list, can't move the divider ...

Ask a question

You must log in to your account to reply to posts. Please start a new question, if you do not have an account yet.