Fullscreen applications breaks under mosh 1.4.0 on MacOS 15.4

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Hello,

I have just received a brand new Air 15 M3 with MacOS Sequoia 15.4, installed mosh 1.4.0 via brew and connected to my Fedora in the MacOS built-in Terminal app.

After some time of editing in Vim the session gets broken, it looks like everything is shifted one line upwards, things are breaking, I am not entirely sure what is wrong. When I delete a line, it deletes a line above the cursor and the status line of vim updates one line below where it should render. Clearing the session with Ctrl-L does not help.

I customized the Terminal a bit in Settings, I will try to revert to default values but wanted to open up this issue first. Here is how it looks like:

I did not have this problem on Pro 16 M1 which also had the same OS version and I also exclusively only used the built-in Terminal app. Not sure what is different, I guess mosh version is new I did not upgrade too often.

For the record, here is my settings of the Terminal.app:

% defaults read com.apple.Terminal
{
    "Default Window Settings" = Basic;
    DefaultProfilesVersion = 1;
    HasMigratedDefaults = 1;
    "NSWindow Frame NSFontPanel" = "889 314 603 289 0 0 1710 1068 ";
    "NSWindow Frame TTAppPreferences" = "712 168 667 568 0 0 1710 1068 ";
    "NSWindow Frame TTWindow" = "77 296 524 355 0 0 1710 1068 ";
    "NSWindow Frame TTWindow Basic" = "0 154 1225 914 0 0 1710 1068 ";
    ProfileCurrentVersion = "2.07";
    SecureKeyboardEntry = 0;
    "Startup Window Settings" = Basic;
    "TTAppPreferences Selected Tab" = 1;
    "Window Settings" =     {
        Basic =         {
            CursorBlink = 1;
            CursorType = 0;
            EnableSmoothResizing = 0;
            Font = {length = 267, bytes = 0x62706c69 73743030 d4010203 04050607 ... 00000000 000000cf };
            FontAntialias = 1;
            FontWidthSpacing = "1.004032258064516";
            ProfileCurrentVersion = "2.07";
            ShouldLimitScrollback = 1;
            ShouldRestoreContent = 0;
            ShowActiveProcessArgumentsInTabTitle = 1;
            ShowActiveProcessArgumentsInTitle = 0;
            ShowActiveProcessInTabTitle = 1;
            ShowCommandKeyInTitle = 0;
            ShowComponentsWhenTabHasCustomTitle = 0;
            ShowDimensionsInTitle = 1;
            ShowRepresentedURLInTabTitle = 0;
            ShowRepresentedURLInTitle = 0;
            ShowRepresentedURLPathInTitle = 0;
            ShowShellCommandInTitle = 0;
            ShowTTYNameInTabTitle = 0;
            ShowTTYNameInTitle = 0;
            ShowWindowSettingsNameInTitle = 0;
            columnCount = 120;
            name = Basic;
            rowCount = 44;
            shellExitAction = 1;
            type = "Window Settings";
            useOptionAsMetaKey = 0;
        };
    };
}

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Tested with stock Terminal.app settings:

defaults delete-all com.apple.Terminal

I am experiencing the same behavior, the session breaks quite quickly in fact resetting the session or Ctrl-L does immediately trigger this misbehavior.

For the record, I just installed iTerm2 and everything works fine. So I guess this is some regression in Terminal.app.