Issue with borderless when using default_tab_template with children

[aidantlynch00]

Basic information
zellij --version: zellij 0.40.1

stty size: 69 281

uname -av or ver(Windows): Linux halcyon 6.2.15-100.fc36.x86_64 SMP PREEMPT_DYNAMIC Thu May 11 16:51:53 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux

Further information

Reproduction steps, noticeable behavior, related issues, etc

2. Issues with the Zellij UI / behavior / crash

Issue description

Layouts that define a default_tab_template with a children node will not respect the borderless=true attribute on children nodes. If the same child pane is instead placed in the default_tab_template in place of children, the expected behavior is seen.

Minimal reproduction

The following layout produces the observed behavior:

layout {
    default_tab_template {
        pane borderless=true size=1 {
            plugin location="tab-bar"
        }
        children
        pane borderless=true size=1 {
            plugin location="status-bar"
        }
    }

    tab {
        pane borderless=true
    }
}

The next layout produces the expected behavior:

layout {
    default_tab_template {
        pane borderless=true size=1 {
            plugin location="tab-bar"
        }
        pane borderless=true
        pane borderless=true size=1 {
            plugin location="status-bar"
        }
    }

    tab
}

Other relevant information

My full layout contains 3 tabs. I have run zellij with this layout many times and usually the pane on the last tab is borderless, however this is not consistent. I have also seen the pane on the 2nd tab be borderless a couple of times. This leads me to believe some race is happening. I have pasted my full layout below for completeness:

layout {
    pane_template name="plain-pane" borderless=true

    default_tab_template {
        plain-pane size=1 {
            plugin location="tab-bar"
        }
        children
        plain-pane size=1 {
            plugin location="status-bar"
        }
    }

    tab name="Code" {
        plain-pane command="nvim"
    }
    
    tab name="Term" focus=true {
        plain-pane
    }

    tab name="Git" {
        plain-pane command="lazygit"
    }
}

Let me know if you would like me to provide more information/examples.