bug: half block characters of headings not following color scheme

[Atlasim1]

Neovim version (nvim -v)

v0.11.3

Neovim distribution

None, Custom Config

Operating system

Linux (endeavouros)

Terminal emulator / GUI

kitty

Describe the bug

The UPPER and LOWER_HALF_BLOCK characters do not follow the same color scheme as the heading line itself.

this may be an issue with my current color scheme (i use "gbprod/nord.nvim"). However, documentation isn't clear enough on how to fix

---

Here, you can also see how the border lines match (with the incorrect colors) when the line is selected.

Expected behavior

The Half block characters should have a uniform color scheme with the heading line

Healthcheck output

==============================================================================
render-markdown:                                                            ✅

render-markdown.nvim [version] ~
- ✅ OK plugin 8.5.1
- ✅ OK neovim >= 0.11

render-markdown.nvim [configuration] ~
- ✅ OK valid

render-markdown.nvim [treesitter] ~
- ✅ OK markdown: parser installed
- ✅ OK markdown: highlights ~/.local/share/nvim/lazy/nvim-treesitter/queries/markdown/highlights.scm
- ✅ OK markdown: highlighter enabled
- ✅ OK markdown_inline: parser installed
- ✅ OK markdown_inline: highlights ~/.local/share/nvim/lazy/nvim-treesitter/queries/markdown_inline/highlights.scm
- ✅ OK html: parser installed

render-markdown.nvim [icons] ~
- ✅ OK using: nvim-web-devicons

render-markdown.nvim [executables] ~

render-markdown.nvim [conflicts] ~
- ✅ OK headlines: not installed
- ✅ OK markview: not installed
- ✅ OK obsidian: not installed

Plugin configuration

{ -- Markdown Rendering
		"MeanderingProgrammer/render-markdown.nvim",
		dependencies = { "nvim-treesitter/nvim-treesitter", "nvim-tree/nvim-web-devicons" },
		opts = {
			heading = {
				border = true,
				border_virtual = true,
			},
			indent = {
				enabled = true,
			},
			latex = {
				enabled = false,
			},
			quote = {
				repeat_linebreak = true,
			},
			win_options = {
				showbreak = {
					default = "",
					rendered = "  ",
				},
				breakindent = {
					default = false,
					rendered = true,
				},
				breakindentopt = {
					default = "",
					rendered = "",
				},
			},
		},
	},


-- Don't you love how yanking converts my 2space indents into indent chars

Plugin error log

Not Applicable

Confirmations

• I have updated this plugin to the latest version using my plugin manager
• I have provided the text contained in all screenshots as raw text in this issue. This means if there is a screenshot below it is the copy pasted contents of the file in the screenshot. I understand that my issue will be closed if I have not.

Additional information

This is probably an issue with the color scheme I'm using, but the docs could be improved on this.

[MeanderingProgrammer]

The heading border highlights are constructed by taking the background highlight group and creating a new highlight group with the foreground set as its background, like reversing but ignoring the foreground values. Using a level 1 heading as an example we'll do something like:

local hl = vim.api.nvim_get_hl(0, { name ='RenderMarkdownH1Bg', link = false })
vim.api.nvim_set_hl(0, 'RenderMarkdownH1Bg_border', {
    fg = hl.bg,
    ctermfg = hl.ctermbg,
})

And use the created highlight group RenderMarkdownH1Bg_border for the border.

There are some color schemes where this may not work for various reasons.

To fix this try changing the values for heading.foregrounds & heading.backgrounds or setting custom values for the default highlight groups RenderMarkdownH1 .. RenderMarkdownH6 & RenderMarkdownH1Bg .. RenderMarkdownH6Bg