2048826 - Folder Pane only opens/closes using the menu and cannot be "sized" in width (or opened/closed) using the mouse

Status: RESOLVED FIXED

(Thunderbird :: Mail Window Front End, defect)

Description

[Stephen]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:152.0) Gecko/20100101 Firefox/152.0

Steps to reproduce:

Here's a link to the discussion in Thunderbird Help so far. https://support.mozilla.org/en-US/questions/1587978?utm_campaign=questions-reply&utm_source=notification&utm_medium=email
In brief, after upgrading to Thunderbird 151.0.1 the folder pane could only be opened/closed/changed (width) for 1 account when there are multiple tabs for each email account. Numerous steps were tried (see link to Help) and the problem persists after removing Thunderbird entirely and clean installing version 152.0. Closing the first account tab to substitute another account the only (first) tab open did not enable that account folder pane to work as in the past.
User Agent String: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:152.0) Gecko/20100101 Firefox/152.0

Actual results:

What happened is prior to version 151.0.1 the folder pane could be opened/closed/changed (width) independently for each tab/account that was opened. In the past as many as 6 accounts worked this way. After an upgrade to 152.0 the folder pane only worked fully for the first open tab/account.

Expected results:

What should happen is the folder pane should be opened/closed with the mouse as well as the menu layout selection and the folder pane should be sizable in width from a wide pane down to any size including closed. When closed a bar became visible when the mouse was hovered over the left hand side of the application window. This used to indicate that the folder pane could be opened with the mouse.

Comment 1

[Stephen]

Bug 2011469 seems related to my issue since I have a multiple tabs/email accounts elements where the folder pane appearance (status) used to vary for each tab but now does not. I had viewed the problem as a border detection issue and not realized that there are multiple folder pane instances: one for each tab/account.

Comment 2

[Ed]

I can confirm: in v152, open one account in one tab, another account in another tab. The folder pane can't be resized with the mouse for either tab. Resizing other tabs is possible in v140.12.0esr.

Comment 3

[Wayne Mery (:wsmwk)]

Related to this?
Error: Warning processing displayedFolder: Support deprecated since Thunderbird 121 and removed in Manifest V3: MailTabProperties.displayedFolder needs to be specified as a MailFolderId instead of as a full MailFolder object. background.js:36
selectInbox moz-extension://388c8c5f-7e28-40fc-91e2-4a81150dd738/background.js:36

Comment 4

[Martin Giger [:freaktechnik]]

(In reply to Wayne Mery (:wsmwk) from comment #3)

Related to this?
Error: Warning processing displayedFolder: Support deprecated since Thunderbird 121 and removed in Manifest V3: MailTabProperties.displayedFolder needs to be specified as a MailFolderId instead of as a full MailFolder object. background.js:36
selectInbox moz-extension://388c8c5f-7e28-40fc-91e2-4a81150dd738/background.js:36

That's for extensions, can you try to reproduce without extensions?

Comment 5

[Wayne Mery (:wsmwk)]

Reproduces in troubleshoot mode 152 and 153 beta.

I do not see anything alarming in the error console

Comment 6

[Hartmut Welpmann [:welpy-cw]]

Attachment: Bug 2048826 - Fix folder pane splitter not working in non-first about3pane tabs. r=#thunderbird-reviewers

The isDisabled setter was changed in bug 2008907 from an if/else that
explicitly removed the disabled attribute for falsy values, to a single
toggleAttribute() call. When syntheticView is undefined (the normal case),
this called toggleAttribute("disabled", undefined), which per DOM spec
toggles the attribute (adds if absent) rather than removing it —
incorrectly disabling the folder pane splitter in any tab opened after
the first.

Fix by coercing the value to boolean before passing to toggleAttribute.

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/comm-central/rev/538a38bc5a02
Fix folder pane splitter not working in non-first about3pane tabs. r=mkmelin,freaktechnik