1754794 - Message preview pane vertical position changes depending on size of message header

Status: RESOLVED WORKSFORME

(Thunderbird :: Mail Window Front End, defect, P4)

Description

[Wayne Mery (:wsmwk)]

Thunderbird 98.0b1 candidate, Mac, safe mode

• classic 3 pane view - When scrolling through message list, the vertical positioning of the message header changes depending on the size of the message header.
• vertical 3 pane view - When scrolling through message list, the horizontal width of the message list changes

Same behavior if I disable the spaces side bar.
I have not tried a new profile.
I have not tried to go back to 97 beta.

Comment 1

[Magnus Melin [:mkmelin]]

I don't understand this bug. Maybe a screenshot could help?

Comment 2

[Wayne Mery (:wsmwk)]

Attachment: Screen Shot 2022-04-12 at 5.57.33 AM.png

For me the issue depends on the size of the message header, i.e. whether the height of the message header is 3, 4 or 5 lines long.

If a messages header displays as 4 lines and I add a tag to the message, then the borders of the message header change at BOTH the top and bottom - moves vertically up and moves down respectively. Only the BOTTOM should move. The position of the top of the header, where it meets the message list, should remain fixed.

Comment 3

[Alessandro Castellani [:aleca]]

Mhh, I can't reproduce this, very strange.
For what you're describing it seems to be related to the XUL splitter.
Would you be able to write detailed steps to reproduce this consistently?

Comment 4

[Maxim Britov]

Attachment: Sample of issue if I right understand this topic

I have issue with new headers size since tb 98.0b1. It seems same as described here.

Comment 6

[Wayne Mery (:wsmwk)]

(In reply to Alessandro Castellani [:aleca] from comment #3)

Mhh, I can't reproduce this, very strange.
For what you're describing it seems to be related to the XUL splitter.
Would you be able to write detailed steps to reproduce this consistently?

From max's excellent description in bug 1766607 ...

Steps to reproduce:

Open in folder with messages having varying number of displayed headers (Cc, etc.), e.g. some real newsgroup.
"Read" several messages paying attention to the position of the splitter between message list and the headers pane.

Actual results:

For messages having more headers the splitter jumps upper, when another message has fewer headers the more compact panes causes a jump to lower level.

Last message visible in the list may disappear and then appear again during the walk through the messages.

Comment 7

[Alessandro Castellani [:aleca]]

This is most likely an issue with the XUL splitter and the message pane, which also comes with some dynamic splitters inside itself in case there are attachments or extra headers.

This will most likely be solved once we switch to the new mail 3 pane and use the new HTML splitters built by Henry.
We can live this open with a low priority, just in case this becomes a very recurring issue and we decide to assign some resources to fix soon to be removed XUL elements, or if for some weird case this issue happens also in the new 3 pane.

Comment 8

[max]

(In reply to Alessandro Castellani [:aleca] from comment #7)

This is most likely an issue with the XUL splitter and the message pane

This bug is a regression in comparison to Thunderbird-91 where upper edge of the headers pane is stable. XUL UI was working better for a long time.

This will most likely be solved once we switch to the new mail 3 pane and use the new HTML splitters built by Henry.

Will it happen before the next ESR? I can not say that this bug is the most annoying one since thunderbird-78, but during search for a particular message in a long threads jumping splitter increases confusion concerning which messages has been checked already. "Third message from the bottom" is an identifier that can be kept in memory for a couple of minutes.

Comment 9

[Wayne Mery (:wsmwk)]

Maxim, max,
Do you still see this when using version 115?

Comment 10

[Maxim Britov]

(In reply to Wayne Mery (:wsmwk) from comment #9)

Maxim, max,
Do you still see this when using version 115?

Can't reproduce on 115

Comment 11

[Wayne Mery (:wsmwk)]

Thanks for the update.
WFM also