I find Vivaldi's implementation very clunky. It has a vertical panel there as well, and they do not play nicely together: they happen to be in the same place but they do not cooperate or interoperate at all.
As an example: in the email client, the folders appear in the side panel, which is conceptually "above" (to the left of) the tabs. (I use English, and in English we read left-to-right, then top-to bottom.) The problem is that in fact, the folders are logically inside the mail tab: they only pertain to the content of a single tab, but they are shown for all tabs.
It is, IMHO, a design mess, and I have tried to convey this to the company, but it seems uninterested.
A second example of neglect of this L-to-R, top-to-bottom rule is GNOME. In GNOME 3 and above, action buttons in dialog boxes appear in the CSD bar at the top... but I have not yet read the contents of the dialog box, so I do not yet know whether I want that action or not. Logically, the buttons should be at the bottom, and grouped together, and this applies equally to R-to-L scripts (such as Hebrew and Arabic) or to writing systems that are conventionally and classically top-to-bottom _then_ side-to-side, such as Chinese and Japanese.
As an example: in the email client, the folders appear in the side panel, which is conceptually "above" (to the left of) the tabs. (I use English, and in English we read left-to-right, then top-to bottom.) The problem is that in fact, the folders are logically inside the mail tab: they only pertain to the content of a single tab, but they are shown for all tabs.
It is, IMHO, a design mess, and I have tried to convey this to the company, but it seems uninterested.
A second example of neglect of this L-to-R, top-to-bottom rule is GNOME. In GNOME 3 and above, action buttons in dialog boxes appear in the CSD bar at the top... but I have not yet read the contents of the dialog box, so I do not yet know whether I want that action or not. Logically, the buttons should be at the bottom, and grouped together, and this applies equally to R-to-L scripts (such as Hebrew and Arabic) or to writing systems that are conventionally and classically top-to-bottom _then_ side-to-side, such as Chinese and Japanese.