Table of contents block ruins heading anchors

I installed this plugin to get a simple table of contents. The TOC block worked well, responds well, and looks nice. I was happy with how it worked overall.

Then I realized it rewrote all of my heading anchors and broke a bunch of links on my page. It has 3 crucial flaws regarding heading anchors

1. The TOC block adds its own anchors to all headings on a page, overwriting user-specified anchors.
2. The generated anchors begin with a number based on the order of headings in the page.
3. The anchors update when I change the text of a heading

For (1) I had specified multiple internal anchor links on my page. After I added the TOC block, they were ALL broken.

(2) Means that I can never reliably link to a heading anchor again. If I have heading 1 and heading 2 and link to heading 2, my link will break if I add a heading between heading 1 and heading 2.

(3) means that if I change the text of a heading, the anchor changes and again my links break.

Please

1. Respect user anchors. If one exists, do NOT overwrite it. A user put it there for a reason.
2. Omit numbers from anchors to minimize churn
3. Once an anchor is set, don’t change it even if the heading text changes