Also see: https://bugzilla.mozilla.org/show_bug.cgi?id=776380

See  Issue 3773 

Could you please post a minimal test case?

There's one attached to the Bugzilla post:

https://google-developers.appspot.com/maps/documentation/javascript/examples/infowindow-simple

Repeatedly hover your cursor over the one mark. Approximately 50% of the time I do not see the label.

I'm running Firefox 20.0.1 on Windows 7 and this bug still exists.

I have a jsbin here with a google map & markers with titles. The titles do not always appear when the mouse hovers over a marker. Moving the mouse away and back over sometimes will cause the title to show up. Generally it shows up the first time and then after that it will not show up consistently. 

http://jsbin.com/eyugib/3

I am also seeing the bug in Firefox 20 on Xubuntu 13.04 running in VirtualBox.

Me too with Firefox 21 with ubuntu 12.04

Do you have an update on when this will be resolved please?

This bug reports is marked as 'need more info'. What is it that you need?
There is a test case here...
http://jsfiddle.net/spiderplant0/smffq/

The bug has also been marked as 'fixed' here.... 
https://code.google.com/p/gmaps-api-issues/issues/detail?id=3773
But it definitely hasnt been fixed.

Me too with Firefox 22.0 on Windows XP SP3.

See   Issue 3749 

https://code.google.com/p/gmaps-api-issues/issues/detail?id=3749

There is also a sample here which demonstrates the bug:

https://developers.google.com/maps/documentation/javascript/examples/streetview-overlays?csw=1

In Firefox, just move the mouse from one marker to the next -- only the first marker is reliable.

Had this issue on Opera and Firefox.
Found that using optimized:false solve it in my case.
However this is not a normal behavior.

see: https://code.google.com/p/gmaps-api-issues/issues/detail?id=3749

 Issue 3749  has been merged into this issue.

In Firefox 38.0.5 on Windows 7 Pro 64-bit, all marker hovers after the first fail to trigger the marker title tooltip. Does not occur with latest Chrome, IE, or Opera.

I'm reproducing this issue in my own app, but more importantly I can reproduce it even at the "Simple markers" example in the API docs:

https://developers.google.com/maps/documentation/javascript/examples/marker-simple

Go to that example, hover on the marker, then move off the marker *but stay on the map*, then hover back on the marker. First hover shows the title tooltip, second hover does not. Now try it again but move the mouse cursor off the map before you do. The tooltip now shows. It seems something is reset during mouseout/mouseover.

As suggested by this article here.

http://stackoverflow.com/questions/25278930/google-map-multiple-marker-tooltip-only-show-on-the-first-marker-in-firefox

The solution to make the tooltip appear correctly on firefox is to add "optimized : false", to the marker definition properties. I can verify that it works correctly as I  have tested this with ff 38.1 on both Linux and Windows.

> add "optimized : false", to the marker definition properties.

Thank you. Also confirmed with Firefox 39 at:
http://jsfiddle.net/msz08tjx/7/
http://geekout.org.uk/map/

> add "optimized : false", to the marker definition properties.

I can also confirm this in Firefox 39. Tested on several websites.

Please note that this property not only solves the issue for the "title: " property of the marker, but it also solves any problems with the mouseover addListener event.

it gets too slow when you have many markers and shape property has strange behaviour whith more than one marker at the same loaction. I'll downgrade firefox.

Safari v. 8.0.8 - Marker "title: " not working in Google Maps demos "Complex marker icons" (multiple markers) or "Simple marker icons" (single marker) code examples, or in my test page (using js?v=3.19&) 

See demo: https://developers.google.com/maps/documentation/javascript/examples/icon-complex

Yes, I can reproduce the issue.

firefox 41.0 ie 8 both have problem, the title only appears on some markers sometimes, after on the first marker for the first time.

Still an issue in Firefox 46.0. The workaround with setting "optimized: false" in the map marker options works (Thanks).

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