[nongnu] elpa/eglot-inactive-regions b81249c566 23/66: Update README with caveats section

[ELPA Syncer]

branch: elpa/eglot-inactive-regions
commit b81249c56646f1b3fd57c3f2f4c36da81cb1988a
Author: Filippo Argiolas <filippo.argiolas@gmail.com>
Commit: Filippo Argiolas <filippo.argiolas@gmail.com>

    Update README with caveats section
---
 README.md | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/README.md b/README.md
index bb5522ee7c..f51267be18 100644
--- a/README.md
+++ b/README.md
@@ -41,3 +41,20 @@ Feedback, issues and pull requests more than welcome!
   (setq clangd-inactive-regions-opacity 0.55)
   (add-hook 'eglot-managed-mode-hook #'clangd-inactive-regions-mode))
 ```
+
+
+## Caveats
+
+As far as I know Emacs doesn't have a way to set foreground text
+opacity. Best would be a face attribute so that you can set it in an
+overlay covering the whole inactive regions and be done with it.
+
+So `darken-foreground` method is a fragile and inefficient hack around
+fontification that for each inactive region looks for symbols with
+different faces and applies to each of them a different overlay with a
+dimmed foreground color.
+
+It seems to work with cc and c-ts modes (albeit a little slower than
+I'd like) but could totally break other modes or features I'm not aware of.
+
+If you know a better way please do let me know.
\ No newline at end of file