On my ipad-1, when I'm online ( through safari, chrome or opera) every two minutes or so the webpage that I am on disappears; the screen first turns black and then returns to the homepage. By touching the icon of the server concerned, the screen returns to the original webpage, but two minutes later the same thing happens again.
All this started two weeks ago, and it is getting worse. Is there any solution for this rather annoying phenomenon? Hendrik Prenger

Try these usual fixes. If you are not doing so, it's a good idea to restart the iPad every so often, once a month or more often if it seems to need it.

Since it is Safari, you can also try going to Settings > Safari and Clear Data and Cookies. You'll have to log back into sites that usually remember your after doing so.

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The usual fixes:

When you have problems with an app it's a good idea to clear it from RAM.

Close/Clear the app: With the problem app closed, double tap on the Home button to get the multitask bar. Tap and hold on any icon in the bar until they jiggle, then tap the minus sign on the problem app. This will remove it from RAM and insure a clean start the next time you launch the app.

If that does not work try a restart,

Restart: Hold down the power button until the power off slider appears. Slide it off. When the iPad finishes shutting down, hold down the power button again until the Apple logo appears. Apple recommends you restart the iPad at least once a month.

and then a reset if that does not work.

Reset: Hold down the power and home buttons until the Apple logo appears. The iPad will reboot. This usually takes a bit longer than a restart. takes a bit longer than a restart.

The restart did indeed solve the problem; many thanks for your assistance. Hendrik Prenger

No problem. Glad it worked.