Double processing after context menu click - google-chrome

Question

I have an extension that inserts text into textarea and similar.
The user can choose text from the popup or the contextmenu.
I have "all_frames" : true so that my content script can see all the iframes - in case a textarea is in an iframe.
After a save to the database (more on this in a bit), if the user uses the contextmenu to add text (handled via messaging from background.js to content.js) to a text area the text is added twice.
If the user uses the popup.html mechanism, which passes text to the same content.js, the text is only entered once (the desired outcomes!).
The message is only passed once by background.js.
For instance, if there are five iframes on a page, and therefore 5 instances of content.js, the contextmenu listener script runs 10 times (not 5, as it should).
If I remove "all_frames" : true from the manifest then the text only adds once.
But I need to keep this setting so I can reach textareas in iFrames. And the popup insert works beautifully everywhere.
The save to the database is what triggers the behavior - and that process is a simple json write to a php file. I wipe the contextmenu as part of that process - but again, it isn't a question of the background.js sending 2 messages. One message is sent, and for some reason the code runs through the messaging routine 2x.
I've tried creating flags to mark once a single successful insertion has happened, but everything is asynch and I don't think this would be helpful even if I could get it to work in some cases.
I feel like I need to kill some old content.js processes or something...
The kicker: if I Reload the Extension (in developer mode) the contextmenu works properly and inserts selected text only once. It's only after I save to the db that the problem occurs.
I'm very close to throwing out contextmenus as a feature and just using the elegant popup.html. But this seems like some weird edge case that would be worth understanding.
Many thanks for taking a look. I've included some code and also a screenshot of the console showing the 10x repeats of the content.js code when inserting into a Google Doc.
background.js
chrome.tabs.query({active: true, currentWindow: true}, function(tabs) {
chrome.tabs.sendMessage(tabs[0].id, {method: "insertComment", comment: tempText}, function(response) {
// console.log(response.status);
});
});
content.js
chrome.runtime.onMessage.addListener(
function(request, sender, sendResponse) {
if (request.method == 'insertComment'){
var sValue = request.comment;
var currentEltag = document.activeElement.tagName.toLowerCase(); //Checking for currently selected area
console.log("currentEltag before logic: " + currentEltag + " / id: " + document.activeElement.id);
console.log("activeTag: " + activeTag);
// console.log("activeEl: " + activeEl.id + ' / name: ' + activeEl.name + ' /value: ' + activeEl.value);
if (activeTag === undefined || activeTag === null){
console.log('currentEltag in logic: ' + currentEltag);
if (currentEltag === 'iframe'){
activeTag = 'iframe';
console.log('Making activeTag equal iframe');
}
}
var sField = activeEl;
if (activeTag === 'input' || activeTag === 'textarea'){
console.log('Dealing with plain input/textarea - yes! sField is: ' + sField);
var nStart = sField.selectionStart;
var nEnd = sField.selectionEnd;
if (nStart || nEnd == '0'){
console.log("Inside insert sub with starting point: " + nStart + ' and end ' + nEnd + ' with value ' + sValue);
console.log('Print and increment...');
sField.value = sField.value.substring(0, nStart) + sValue + sField.value.substring(nEnd, sField.value.length);
sField.selectionStart = nStart + sValue.length;
sField.selectionEnd = nStart + sValue.length;
console.log('Printed value1...and flag is now: ');
chrome.storage.sync.get("flag", function(data) {
console.log("Flag", data.flag);
});
}
else {
sField.value = sValue;
console.log('Printed value2...');
}
} //End if input or textarea