Surrounding a block select with spaces doesn't work

[idbrii]

I can surround a block selection with braces, but not spaces.

I tried this on v1.90 as well as v2.2 and the same result with both, so I guess this was never supported?

Problem

I have some text and I'd like spaces around the ..:

tags[id..def.type] = true
tags[id..def.name] = true

I block select the column of .. (f.<C-q>lj) and surround with space (S<space><space>). Nothing changes. If surround with ) then it works. I have the same results when surrounding a block selection of letters too.

Expected result:

tags[id .. def.type] = true
tags[id .. def.name] = true

I can usually surround with spaces (by inputting space twice): ys2w<space><space>. Not sure why it doesn't work in this case.

Environment

I tried with clean setups:

nvim --clean -u ~/.vim/bundle/surround/plugin/surround.vim  ~/test.txt
vim --clean -N -u ~/.vim/bundle/surround/plugin/surround.vim ~/test.txt

Versions

vim-surround@ aeb9332

NVIM v0.11.1
Build type: Release
LuaJIT 2.1.1741730670

VIM - Vi IMproved 9.0 (2022 Jun 28, compiled May 24 2023 22:50:33)
MS-Windows 64-bit console version
Included patches: 1-1576

[tpope]

Can confirm that I can reproduce the failure in visual blockwise mode.