Even the most durable energy-saving lamp burns out sooner or later. If this happens, you can, if you wish, assemble a new one in its body - this time, although low-power, but maintainable.
Turn off the light with the switch. Remove the burnt out energy-saving lamp from it.
Allow the lamp to soak for two days to fully discharge the storage capacitor. At the same time, take an unnecessary but serviceable cell phone charger and also keep it unplugged for two days for the same purpose.
After the end of exposure, carefully open the housings of both the lamp and the charger. Be careful not to depressurize the flask. Separate the flask (it is glued) and hand it over to a mercury waste collection point.
Remove the boards from the lamp and charger. Set aside the lamp board and use it as a source of radio components. Move the board from the charger to the lamp housing. Connect its input, designed for supplying mains voltage, to the base from the inside.
Make four strings in series, each consisting of two 20mA LEDs of the desired color and one 200Ω 0.5W resistor. Connect all chains in parallel and connect, observing the polarity, to the output of the charger board. Place all this in a separate housing, which you glue to the upper half of the lamp housing. Close the lamp housing itself, having previously taken measures to exclude the board displacement, which threatens a meek circuit. Also exclude any possibility of touching live parts.
Screw the lamp into the fixture and start using it.
LEDs in such a lamp work in a light mode, and therefore it will not shine brightly, but their service life will be significant. If a malfunction occurs in the lamp, simply unplug and turn it out, again withstand two days without voltage, then replace the damaged LED or board (or repair the last one if you know how to troubleshoot telephone chargers). Then reassemble the lamp.