What is an inactive_sections?

[SephVelut]

Not documented?

[fitrh]

Section to put your component which is displayed when the window is not focused

[fitrh]

[nyngwang]

Is it possible to disable lualine for all inactive windows?

[fitrh]

Since 'laststatus' is a global option, I think the best we can do to imitate
a disabled statusline is to set inactive highlight to Normal and
inactive_sections.lualine_* to empty

[nyngwang]

I just realized that there is an option vim.opt.laststatus = 3 that is exactly what I want. Still appreciate your attempt to help :)

[fitrh]

Ah, so you mean single status line

Yes, that option is available for a while now, from lualine, you can use options.globalstatus = true, which is the same as vim.opt.laststatus = 3