Steps to Reproduce

Scenario A (SWF File)

1. Create a test page. Let's name it "Multimedia Macro Test".
2. Edit the page.
3. Attach a SWF file. You may use the attached sample - ClearExternalNoVol.swf.
4. Insert the Multimedia macro via "+" sign > Other Macros and select the attached SWF file from Step 3.
5. The SWF file should be rendered correctly.
6. Edit the page again and add a colon ":" in the page title.
7. Save the page again and you will notice that the SWF file is still rendered correctly.
8. Edit the page once again and click Edit on the Multimedia macro properties.
9. Hit Save without editing any parameters.
10. Observe the error returned.
    MultimediaMacroTest1.mp4

Scenario B (MP4 File)

1. Create a test page. Let's name it "Multimedia Macro Test".
2. Edit the page.
3. Attach a MP4 file. You may use the attached sample - Test.mp4.
4. Insert the Multimedia macro via "+" sign > Other Macros and select the attached MP4 file from Step 3.
5. The MP4 file should be rendered correctly.
6. Edit the page again and add a colon ":" in the page title.
7. Save the page.
8. Observe the error returned.
   MultimediaMacroTest2.mp4

Expected Behaviour

Multimedia file rendered correctly.

Actual Behaviour

The page returns the following error.

Error rendering macro 'multimedia' : com.atlassian.renderer.v2.macro.MacroException: Cannot find attachment '<attachment>'