Kee fills the Browser console with messages about undefined p.sender.tab

According to this bug report extensions shouldn’t be triggering this. I’m not sure how to identify if it’s Kee or Firefox, since Firefox now requires to install the developer version of Firefox to install unsigned extensions and my workflow makes that difficult. I noticed this because Kee was refusing to fill the form in a tab. That problem went away but the message keeps spamming, which made diagnosticing the issue confusing.

That could be coming from Kee but as you guessed, problems with Firefox might be the root cause. Do you see the same behaviour with both Kee 3.2 and 3.4 (the current beta version)?

Still the same behavior. The message occurs every 5 seconds. I’m using firefox 78.0.1 on Debian testing.

This could be why there is tab undefined in last post of Constant CPU usage, increasing memory usage, killing the browser

There is this code:
browser.tabs.onUpdated.addListener((tabId, changeInfo, tabInfo) => {

function onFound(tabs) {
	**let tab = tabs[0];**

Mozilla have fixed a bug (in v84) that might have led to errors relating to tab communications failing. Will be interesting to see in future if this specific error message no longer appears.