user26717: Just discovered that long after uninstalling Dropbox the service was still running.  I disabled it in the normal Services control panel.  It turned out to be hiding in /winndows/system32 as dbxsvc.exe
Then went a step further and did this in an Administrator CMD window:
cd /windows/system32
attrib -h -s dbxsv*.*
del dbxsvc.exe
copy con dbxsvc.exe
Nyah^Z
attrib +r dbxsvc.exe

So that should take care of that.
Upon further system searching (using Everything) discovered that Dropbox is used by software called Temboo, which is some kind of cloud-share package for coordinating Arduino Yun applications.
It turned out that it was the Arduino IDE that kept it running. 
More searching led me here:
Arduino & Temboo: How It Works
Excerpt:

ON YOUR YÚN Your Arduino Yún includes two lightweight software
  components that make it easy to connect with hundreds of APIs and
  cloud services from any sketch.
First, there's a small C++ library called Temboo.cpp that comes
  bundled with the Arduino IDE. When you include this library in a
  sketch, it provides a streamlined syntax for configuring and invoking
  calls to run Temboo Choreos.
Behind the scenes, calls to Temboo are routed to a client program that
  comes packaged with your Linino base image. This client is a Python
  program that formats the Choreo execution request and uses HTTPS to
  forward the request to Temboo via the cURL utility.
THE TEMBOO PLATFORM Temboo is a scalable, fault-tolerant environment
  for running and managing smart code snippets that we call Choreos.
  Choreos can call APIs, simplify the OAuth process, send email
  messages, perform encoding, update databases, and lots more. You can
  even create your own custom Choreos. Temboo automatically generates
  the sketch code you needed to call these processes, making it simple
  to get up and running with any service from your Yún.
The request from the Yún's temboo client causes the Choreo specified
  in your sketch code to be executed on the Temboo platform. In many
  cases, this means assembling your inputs into the format expected by a
  third-party API, performing the API interaction, handling errors, and
  dispatching filtered results back to the Yún via HTTPS. The results
  are made available to your Arduino sketch by way of Process’s Stream
  methods.

I only use the standard Arduino IDE and regular Arduino Unos and Nanos.  Sure some are Chinese-made, and some use the CH340 connection type.  
I do not want my system reaching out through the firewall to any cloud-based services, nor do I appreciate that the Arduino IDE thwarted my earlier effort to disable and remove Dropbox.
I get that it came bundled with the standard Arduino IDE.
So my question is whether anyone knows if it will damage anything if I remove this junkware? 
--ADDENDUM - Why to dump Dropbox:
The Dropbox hack is real
Excerpt:

Motherboard reported on what had been rumoured for some time, namely
  that Dropbox had been hacked. 
Not just a little bit hacked and not in
  that "someone has cobbled together a list of credentials that work on
  Dropbox" hacked either, but proper hacked to the tune of 68 million
  records. 
Very shortly after, a supporter of Have I been pwned (HIBP)
  sent over the data which once unzipped, looked like this:
(The Dropbox data across 4 text files)
What we've got here is two files with email address and bcrypt hashes
  then another two with email addresses and SHA1 hashes. It's a
  relatively even distribution of the two which appears to represent a
  transition from the weaker SHA variant to bcrypt's adaptive workload
  approach at some point in time. Only half the accounts get the "good"
  algorithm but here's the rub: the bcrypt accounts include the salt
  whilst the SHA1 accounts don't. It's just as well because it would be
  a far more trivial exercise to crack the older algorithm but without
  the salts, it's near impossible.
At first glance the data looks legit and indeed the Motherboard
  article above quotes a Dropbox employee as confirming it.


user4143: There is no Dropbox software included with ANY version of the Arduino IDE, nor installed on any Linux based Arduino board.
That is not how Temboo and Dropbox work.
You have Temboo as a (source code) library which you can compile into your sketch, and as a user-agent that runs on the Linux portion of the Yùn. That then forwards a request to the Temboo web servers detailing what operations you want to perform on what services.
It is then the Temboo web servers that connect to Dropbox (or whatever service you want to use) and perform operations on your behalf.
If you have Dropbox software installed on your computer it is not the fault of the Arduino IDE.

26717: <p>Just discovered that long after uninstalling Dropbox the service was still running.  I disabled it in the normal Services control panel.  It turned out to be hiding in /winndows/system32 as dbxsvc.exe</p>

<p>Then went a step further and did this in an Administrator CMD window:</p>

<pre><code>cd /windows/system32
attrib -h -s dbxsv*.*
del dbxsvc.exe
copy con dbxsvc.exe
Nyah^Z
attrib +r dbxsvc.exe
</code></pre>

<p>So that should take care of that.</p>

<p>Upon further system searching (using <a href="https://www.voidtools.com/" rel="nofollow noreferrer">Everything</a>) discovered that Dropbox is used by software called Temboo, which is some kind of cloud-share package for coordinating Arduino Yun applications.</p>

<p><strong>It turned out that it was the Arduino IDE that kept it running.</strong>  </p>

<p>More searching led me here:</p>

<p><a href="https://temboo.com/arduino/yun/yun-and-temboo" rel="nofollow noreferrer">Arduino &amp; Temboo: How It Works</a></p>

<p>Excerpt:</p>

<blockquote>
  <p>ON YOUR YÚN Your Arduino Yún includes two lightweight software
  components that make it easy to connect with hundreds of APIs and
  cloud services from any sketch.</p>
  
  <p>First, there's a small C++ library called Temboo.cpp that comes
  bundled with the Arduino IDE. When you include this library in a
  sketch, it provides a streamlined syntax for configuring and invoking
  calls to run Temboo Choreos.</p>
  
  <p>Behind the scenes, calls to Temboo are routed to a client program that
  comes packaged with your Linino base image. This client is a Python
  program that formats the Choreo execution request and uses HTTPS to
  forward the request to Temboo via the cURL utility.</p>
  
  <p>THE TEMBOO PLATFORM Temboo is a scalable, fault-tolerant environment
  for running and managing smart code snippets that we call Choreos.
  Choreos can call APIs, simplify the OAuth process, send email
  messages, perform encoding, update databases, and lots more. You can
  even create your own custom Choreos. Temboo automatically generates
  the sketch code you needed to call these processes, making it simple
  to get up and running with any service from your Yún.</p>
  
  <p>The request from the Yún's temboo client causes the Choreo specified
  in your sketch code to be executed on the Temboo platform. In many
  cases, this means assembling your inputs into the format expected by a
  third-party API, performing the API interaction, handling errors, and
  dispatching filtered results back to the Yún via HTTPS. The results
  are made available to your Arduino sketch by way of Process’s Stream
  methods.</p>
</blockquote>

<p>I only use the standard Arduino IDE and regular Arduino Unos and Nanos.  Sure some are Chinese-made, and some use the CH340 connection type.  </p>

<h2>I do not want my system reaching out through the firewall to any cloud-based services, nor do I appreciate that the Arduino IDE thwarted my earlier effort to disable and remove Dropbox.</h2>

<p><strong>I get that it came bundled with the standard Arduino IDE.</strong></p>

<p><strong>So my question is whether anyone knows if it will damage anything if I remove this junkware?</strong>  </p>

<p>--ADDENDUM - Why to dump Dropbox:</p>

<p><a href="https://www.troyhunt.com/the-dropbox-hack-is-real/" rel="nofollow noreferrer">The Dropbox hack is real</a></p>

<p>Excerpt:</p>

<blockquote>
  <p>Motherboard reported on what had been rumoured for some time, namely
  that Dropbox had been hacked. </p>
  
  <p>Not just a little bit hacked and not in
  that "someone has cobbled together a list of credentials that work on
  Dropbox" hacked either, but proper hacked to the tune of 68 million
  records. </p>
  
  <p>Very shortly after, a supporter of Have I been pwned (HIBP)
  sent over the data which once unzipped, looked like this:</p>
  
  <p>(The Dropbox data across 4 text files)</p>
  
  <p>What we've got here is two files with email address and bcrypt hashes
  then another two with email addresses and SHA1 hashes. It's a
  relatively even distribution of the two which appears to represent a
  transition from the weaker SHA variant to bcrypt's adaptive workload
  approach at some point in time. Only half the accounts get the "good"
  algorithm but here's the rub: the bcrypt accounts include the salt
  whilst the SHA1 accounts don't. It's just as well because it would be
  a far more trivial exercise to crack the older algorithm but without
  the salts, it's near impossible.</p>
  
  <p>At first glance the data looks legit and indeed the Motherboard
  article above quotes a Dropbox employee as confirming it.</p>
</blockquote>
 4143: <p>There is <strong>no</strong> Dropbox software included with ANY version of the Arduino IDE, nor installed on any Linux based Arduino board.</p>

<p>That is <strong>not</strong> how Temboo and Dropbox work.</p>

<p>You have Temboo as a (source code) library which you can compile into your sketch, and as a user-agent that runs on the Linux portion of the Yùn. That then forwards a request to the Temboo web servers detailing what operations you want to perform on what services.</p>

<p><strong>It is then the Temboo web servers that connect to Dropbox (or whatever service you want to use) and perform operations on your behalf.</strong></p>

<p>If you have Dropbox software installed on your computer <strong>it is not the fault of the Arduino IDE.</strong></p>
