user41598: 1. Summary
I would like to add a «Donate» Bitcoin button on my README.md file located on my GitHub repository.

2. Not helped
2.1. Manually button
HTML-code using bitcoin protocol:
<a href="bitcoin:1DF9jgzftTFn4ZnDV2YEjUtZ3uHtBywj57?label=In%20the%20treatment%20of%20Sasha's%20teeth&amp;amount=0.0037"><img src="https://www.drupal.org/files/project-images/bitcoindonate.png" alt="Bitcoin Donate Button"></a>

It's work on HTML page of my GitHub Pages site, demonstration.
But in .md GitHub files not one codes of Meta Stack Exchange answer not work for bitcoin protocol, demonstration.
<a href="bitcoin:1DF9jgzftTFn4ZnDV2YEjUtZ3uHtBywj57?label=In%20the%20treatment%20of%20Sasha's%20teeth&amp;amount=0.0037"><img src="https://www.drupal.org/files/project-images/bitcoindonate.png" alt="Bitcoin Donate Button"></a>

[**![Bitcoin Donate Button**](https://www.drupal.org/files/project-images/bitcoindonate.png)](bitcoin:1DF9jgzftTFn4ZnDV2YEjUtZ3uHtBywj57?label=In%20the%20treatment%20of%20Sasha's%20teeth&amp;amount=0.0037)

<a href="bitcoin:1DF9jgzftTFn4ZnDV2YEjUtZ3uHtBywj57?label=In%20the%20treatment%20of%20Sasha's%20teeth&amp;amount=0.0037">![Bitcoin Donate Button](https://www.drupal.org/files/project-images/bitcoindonate.png)</a>

2.2. Third-party
JavaScript not supported on GitHub README.md pages. By this reason doesn't help me:

Bitcoinate
Bitcoin donate
Leo Bogert simple button


user41598: 1. Demonstration

Click to donate button on page:
https://github.com/KristinitaTest/KristinitaTest.github.io/blob/master/donate/README.md
Link must be opened in your Bitcoin client, example:


2. Relevance
This answer is relevant for April 2018. In the future, the data of this answer may be obsolete.

3. Redirect
You need to use redirect.
User click on Donate button → is redirected to Bitcoin-Redirect page in current tab → then opened bitcoin wallet of user → in current tab is opened page, on which Donate button is situated.

4. Details
4.1. Source of Donate button
[![Bitcoin Donate Button](https://i.stack.imgur.com/MnQ6V.png)](http://KristinitaTest.github.io/donate/Bitcoin-Redirect)

If you click the image, you will go to a page http://KristinitaTest.github.io/donate/Bitcoin-Redirect. See answer on Meta Stack Exchange, how use Markdown markup for this construction. Alternative worked HTML source:
<a href="http://KristinitaTest.github.io/donate/Bitcoin-Redirect"><img src="https://i.stack.imgur.com/MnQ6V.png"></a>

4.2. Source of Bitcoin-Redirect page
<script>
window.location.href = "bitcoin:17uctxtsWG3gpyAy6iJ8AVd5rdSjkJH2?label=In%20the%20treatme0of%20Sasha's%20teeth&amp;amount=0.0037";
history.back();
</script>

Use JavaScript methods window.location.href and history.back.

41598: <h2>1. Summary</h2>

<p>I would like to add a «Donate» Bitcoin button on my <code>README.md</code> file located on my GitHub repository.</p>

<hr>

<h2>2. Not helped</h2>

<h3>2.1. Manually button</h3>

<p>HTML-code using bitcoin protocol:</p>



<pre><code>&lt;a href="bitcoin:1DF9jgzftTFn4ZnDV2YEjUtZ3uHtBywj57?label=In%20the%20treatment%20of%20Sasha's%20teeth&amp;amp;amount=0.0037"&gt;&lt;img src="https://www.drupal.org/files/project-images/bitcoindonate.png" alt="Bitcoin Donate Button"&gt;&lt;/a&gt;
</code></pre>

<p>It's work on HTML page of my GitHub Pages site, <a href="https://kristinitatest.github.io/donate/Bitcoin-HTML-Demo.html" rel="nofollow noreferrer"><strong>demonstration</strong></a>.</p>

<p>But in <code>.md</code> GitHub files not one <a href="https://meta.stackexchange.com/a/38917/326972"><strong>codes of Meta Stack Exchange answer</strong></a> not work for bitcoin protocol, <a href="https://github.com/KristinitaTest/KristinitaTest.github.io/blob/master/donate/Bitcoin-Protocol-Markdown.md" rel="nofollow noreferrer"><strong>demonstration</strong></a>.</p>



<pre><code>&lt;a href="bitcoin:1DF9jgzftTFn4ZnDV2YEjUtZ3uHtBywj57?label=In%20the%20treatment%20of%20Sasha's%20teeth&amp;amp;amount=0.0037"&gt;&lt;img src="https://www.drupal.org/files/project-images/bitcoindonate.png" alt="Bitcoin Donate Button"&gt;&lt;/a&gt;

[**![Bitcoin Donate Button**](https://www.drupal.org/files/project-images/bitcoindonate.png)](bitcoin:1DF9jgzftTFn4ZnDV2YEjUtZ3uHtBywj57?label=In%20the%20treatment%20of%20Sasha's%20teeth&amp;amp;amount=0.0037)

&lt;a href="bitcoin:1DF9jgzftTFn4ZnDV2YEjUtZ3uHtBywj57?label=In%20the%20treatment%20of%20Sasha's%20teeth&amp;amp;amount=0.0037"&gt;![Bitcoin Donate Button](https://www.drupal.org/files/project-images/bitcoindonate.png)&lt;/a&gt;
</code></pre>

<h3>2.2. Third-party</h3>

<p><a href="https://stackoverflow.com/a/21340902/5951529"><strong>JavaScript not supported on GitHub README.md pages</strong></a>. By this reason doesn't help me:</p>

<ul>
<li><a href="http://bitcoinate.org/" rel="nofollow noreferrer"><strong>Bitcoinate</strong></a></li>
<li><a href="https://github.com/danielquinn/bitcoin-donate" rel="nofollow noreferrer"><strong>Bitcoin donate</strong></a></li>
<li><a href="http://wayback.archive.org/web/20130621033546/http://leo.bogert.de/2012/02/22/simple-bitcoin-donate-button/" rel="nofollow noreferrer"><strong>Leo Bogert simple button</strong></a></li>
</ul>
 41598: <h2>1. Demonstration</h2>

<p><img src="https://KristinitaTest.github.io/donate/Bitcoin-Donate-button.png" alt="Donate button"></p>

<p>Click to donate button on page:</p>

<p><strong><a href="https://github.com/KristinitaTest/KristinitaTest.github.io/blob/master/donate/README.md" rel="nofollow noreferrer">https://github.com/KristinitaTest/KristinitaTest.github.io/blob/master/donate/README.md</a></strong></p>

<p>Link must be opened in your Bitcoin client, example:</p>

<p><img src="https://i.imgur.com/YddiVUZ.png" alt="Electrum"></p>

<hr>

<h2>2. Relevance</h2>

<p>This answer is relevant for April 2018. In the future, the data of this answer may be obsolete.</p>

<hr>

<h2>3. Redirect</h2>

<p>You need to use redirect.</p>

<p>User click on <code>Donate</code> button → is redirected to <code>Bitcoin-Redirect</code> page in current tab → then opened bitcoin wallet of user → in current tab is opened page, on which <code>Donate</code> button is situated.</p>

<hr>

<h2>4. Details</h2>

<h3>4.1. Source of <code>Donate</code> button</h3>



<pre><code>[![Bitcoin Donate Button](https://i.stack.imgur.com/MnQ6V.png)](http://KristinitaTest.github.io/donate/Bitcoin-Redirect)
</code></pre>

<p>If you click the image, you will go to a page <strong><a href="http://KristinitaTest.github.io/donate/Bitcoin-Redirect" rel="nofollow noreferrer">http://KristinitaTest.github.io/donate/Bitcoin-Redirect</a></strong>. See <a href="https://meta.stackexchange.com/a/38917/326972"><strong>answer on Meta Stack Exchange</strong></a>, how use Markdown markup for this construction. Alternative worked HTML source:</p>



<pre><code>&lt;a href="http://KristinitaTest.github.io/donate/Bitcoin-Redirect"&gt;&lt;img src="https://i.stack.imgur.com/MnQ6V.png"&gt;&lt;/a&gt;
</code></pre>

<h3>4.2. Source of <code>Bitcoin-Redirect</code> page</h3>



<pre><code>&lt;script&gt;
window.location.href = "bitcoin:17uctxtsWG3gpyAy6iJ8AVd5rdSjkJH2?label=In%20the%20treatme0of%20Sasha's%20teeth&amp;amp;amount=0.0037";
history.back();
&lt;/script&gt;
</code></pre>

<p>Use JavaScript methods <a href="http://javascript.ru/window-location" rel="nofollow noreferrer"><strong>window.location.href</strong></a> and <a href="http://javascript.ru/window.history" rel="nofollow noreferrer"><strong>history.back</strong></a>.</p>
